Author: "Pollard, K. R." / Database: OAIster - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Pollard, K. R."' showing total 129 results

Start Over Author "Pollard, K. R." Database OAIster

129 results on '"Pollard, K. R."'

1. TESS Cycle 1 observations of roAp stars with 2-min cadence data

Author: Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O, Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C C, Mikołajczyk, P, Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K R, Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B, Stateva, I., Vanderspek, R, Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O, Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C C, Mikołajczyk, P, Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K R, Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B, Stateva, I., and Vanderspek, R
Abstract: We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp stars. Amongst these stars we discover the roAp star with the longest pulsation period, another with the shortest rotation period, and six with multiperiodic variability. In addition to these new roAp stars, we present an analysis of 44 known roAp stars observed by TESS during Cycle 1, providing the first high-precision and homogeneous sample of a significant fraction of the known roAp stars. The TESS observations have shown that almost 60 per cent (33) of our sample of stars are multiperiodic, providing excellent cases to test models of roAp pulsations, and from which the most rewarding asteroseismic results can be gleaned. We report four cases of the occurrence of rotationally split frequency multiplets that imply different mode geometries for the same degree modes in the same star. This provides a conundrum in applying the oblique pulsator model to the roAp stars. Finally, we report the discovery of non-linear mode interactions in α Cir (TIC 402546736, HD 128898) around the harmonic of the principal mode – this is only the second case of such a phenomenon.
Published: 2021

2. TESS Cycle 1 observations of roAp stars with 2-min cadence data

Author: Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C. C., Mikołajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B., Stateva, I., Vanderspek, R., Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C. C., Mikołajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B., Stateva, I., and Vanderspek, R.
Abstract: We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp stars. Amongst these stars we discover the roAp star with the longest pulsation period, another with the shortest rotation period, and six with multiperiodic variability. In addition to these new roAp stars, we present an analysis of 44 known roAp stars observed by TESS during Cycle 1, providing the first high-precision and homogeneous sample of a significant fraction of the known roAp stars. The TESS observations have shown that almost 60 per cent (33) of our sample of stars are multiperiodic, providing excellent cases to test models of roAp pulsations, and from which the most rewarding asteroseismic results can be gleaned. We report four cases of the occurrence of rotationally split frequency multiplets that imply different mode geometries for the same degree modes in the same star. This provides a conundrum in applying the oblique pulsator model to the roAp stars. Finally, we report the discovery of non-linear mode interactions in $\alpha$ Cir (TIC 402546736, HD 128898) around the harmonic of the principal mode -- this is only the second case of such a phenomenon., Comment: Accepted for publication in MNRAS. 38 Pages, 50 Figures, 1 Table, 2 Appendices
Published: 2021
Full Text: View/download PDF

3. TESS cycle 1 observations of roAp stars with 2-min cadence data

Author: Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V, Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, Oleg, Niemczura, E., Ozuyar, D., Shi, F., Szabo, R., Samadi-Ghadim, A., Bognar, Zs, Fox-Machado, L., Khalack, V, Lares-Martiz, M., Lovekin, C. C., Mikolajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sodor, A., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Garcia Hernandez, A., Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramon-Ballesta, A., Smalley, B., Stateva, I, Vanderspek, R., Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V, Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, Oleg, Niemczura, E., Ozuyar, D., Shi, F., Szabo, R., Samadi-Ghadim, A., Bognar, Zs, Fox-Machado, L., Khalack, V, Lares-Martiz, M., Lovekin, C. C., Mikolajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sodor, A., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Garcia Hernandez, A., Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramon-Ballesta, A., Smalley, B., Stateva, I, and Vanderspek, R.
Abstract: We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp stars. Amongst these stars we discover the roAp star with the longest pulsation period, another with the shortest rotation period, and six with multiperiodic variability. In addition to these new roAp stars, we present an analysis of 44 known roAp stars observed by TESS during Cycle 1, providing the first high-precision and homogeneous sample of a significant fraction of the known roAp stars. The TESS observations have shown that almost 60 percent (33) of our sample of stars are multiperiodic, providing excellent cases to test models of roAp pulsations, and from which the most rewarding asteroseismic results can be gleaned. We report four cases of the occurrence of rotationally split frequency multiplets that imply different mode geometries for the same degree modes in the same star. This provides a conundrum in applying the oblique pulsator model to the roAp stars. Finally, we report the discovery of non-linear mode interactions in alpha Cir (TIC402546736, HD128898) around the harmonic of the principal mode - this is only the second case of such a phenomenon.
Published: 2021
Full Text: View/download PDF

4. TESS Cycle 1 observations of roAp stars with 2-min cadence data

Author: Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C. C., Mikołajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B., Stateva, I., Vanderspek, R., Holdsworth, D. L., Cunha, M. S., Kurtz, D. W., Antoci, V., Hey, D. R., Bowman, D. M., Kobzar, O., Buzasi, D. L., Kochukhov, O., Niemczura, E., Ozuyar, D., Shi, F., Szabó, R., Samadi-Ghadim, A., Bognár, Zs., Fox-Machado, L., Khalack, V., Lares-Martiz, M., Lovekin, C. C., Mikołajczyk, P., Mkrtichian, D., Pascual-Granado, J., Paunzen, E., Richey-Yowell, T., Sódor, Á., Sikora, J., Yang, T. Z., Brunsden, E., David-Uraz, A., Derekas, A., Hernández, A. García, Guzik, J. A., Hatamkhani, N., Handberg, R., Lambert, T. S., Lampens, P., Murphy, S. J., Monier, R., Pollard, K. R., Quitral-Manosalva, P., Ramón-Ballesta, A., Smalley, B., Stateva, I., and Vanderspek, R.
Abstract: We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp stars. Amongst these stars we discover the roAp star with the longest pulsation period, another with the shortest rotation period, and six with multiperiodic variability. In addition to these new roAp stars, we present an analysis of 44 known roAp stars observed by TESS during Cycle 1, providing the first high-precision and homogeneous sample of a significant fraction of the known roAp stars. The TESS observations have shown that almost 60 per cent (33) of our sample of stars are multiperiodic, providing excellent cases to test models of roAp pulsations, and from which the most rewarding asteroseismic results can be gleaned. We report four cases of the occurrence of rotationally split frequency multiplets that imply different mode geometries for the same degree modes in the same star. This provides a conundrum in applying the oblique pulsator model to the roAp stars. Finally, we report the discovery of non-linear mode interactions in $\alpha$ Cir (TIC 402546736, HD 128898) around the harmonic of the principal mode -- this is only the second case of such a phenomenon., Comment: Accepted for publication in MNRAS. 38 Pages, 50 Figures, 1 Table, 2 Appendices
Published: 2021
Full Text: View/download PDF

5. HD 76920b pinned down: a detailed analysis of the most eccentric planetary system around an evolved star

Author: Bergmann, C., Jones, M. I., Zhao, J., Mustill, A. J., Brahm, R., Torres, P., Wittenmyer, R. A., Gunn, F., Pollard, K. R., Zapata, A., Vanzi, L., Wang, Songhu, Bergmann, C., Jones, M. I., Zhao, J., Mustill, A. J., Brahm, R., Torres, P., Wittenmyer, R. A., Gunn, F., Pollard, K. R., Zapata, A., Vanzi, L., and Wang, Songhu
Abstract: We present 63 new multi-site radial velocity measurements of the K1III giant HD 76920, which was recently reported to host the most eccentric planet known to orbit an evolved star. We focussed our observational efforts on the time around the predicted periastron passage and achieved near-continuous phase coverage of the corresponding radial velocity peak. By combining our radial velocity measurements from four different instruments with previously published ones, we confirm the highly eccentric nature of the system, and find an even higher eccentricity of $e=0.8782 \pm 0.0025$, an orbital period of $415.891^{+0.043}_{-0.039}\,\mathrm{d}$, and a minimum mass of $3.13^{+0.41}_{-0.43}\,\mathrm{M_J}$ for the planet. The uncertainties in the orbital elements are greatly reduced, especially for the period and eccentricity. We also performed a detailed spectroscopic analysis to derive atmospheric stellar parameters, and thus the fundamental stellar parameters ($M_*, R_*, L_*$), taking into account the parallax from Gaia DR2, and independently determined the stellar mass and radius using asteroseismology. Intriguingly, at periastron the planet comes to within 2.4 stellar radii of its host star's surface. However, we find that the planet is not currently experiencing any significant orbital decay and will not be engulfed by the stellar envelope for at least another $50-80$ Myr. Finally, while we calculate a relatively high transit probability of $16\%$, we did not detect a transit in the TESS photometry., Comment: 15 pages, 12 figures, 5 tables, accepted for publication in PASA
Published: 2021
Full Text: View/download PDF

6. Frequency and mode identification of {\gamma} Doradus from photometric and spectroscopic observations

Author: Brunsden, E., Pollard, K. R., Wright, D. J., De Cat, P., Cottrell, P. L., Brunsden, E., Pollard, K. R., Wright, D. J., De Cat, P., and Cottrell, P. L.
Abstract: The prototype star for the {\gamma} Doradus class of pulsating variables was studied em- ploying photometric and spectroscopic observations to determine the frequencies and modes of pulsation. The four frequencies found were self-consistent between the obser- vation types and almost identical to those found in previous studies (1.3641 d-1 ,1.8783 d-1 , 1.4742 d-1 and 1.3209 d-1). Three of the frequencies are classified as l, m = (1, 1) pulsations and the other is ambiguous between l = 2 modes. Two frequencies are shown to be stable over twenty years since their first identification. The agreement in ground-based work makes this star an excellent calibrator for the upcoming TESS observations and a standard for continued asteroseismic modelling., Comment: Accepted for Publication in Monthly Notices of the Royal Astronomical Society, Volume 475, Issue 3, p.3813-3822
Published: 2018
Full Text: View/download PDF

7. The First Planetary Microlensing Event with Two Microlensed Source Stars

Author: Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J.-P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. M., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, Daisuke, Tristram, P. J., Yonehara, A., Szymański, M. K., Poleski, R., Soszyński, I., Ulaczyk, K., Wyrzykowski, Ł., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J.-B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J.-P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. M., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, Daisuke, Tristram, P. J., Yonehara, A., Szymański, M. K., Poleski, R., Soszyński, I., Ulaczyk, K., Wyrzykowski, Ł., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J.-B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: 著者人数: 68名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 小林, 大輔), Accepted: 2018-02-06
Published: 2018

8. Frequency and mode identification of {\gamma} Doradus from photometric and spectroscopic observations

Author: Brunsden, E., Pollard, K. R., Wright, D. J., De Cat, P., Cottrell, P. L., Brunsden, E., Pollard, K. R., Wright, D. J., De Cat, P., and Cottrell, P. L.
Abstract: The prototype star for the {\gamma} Doradus class of pulsating variables was studied em- ploying photometric and spectroscopic observations to determine the frequencies and modes of pulsation. The four frequencies found were self-consistent between the obser- vation types and almost identical to those found in previous studies (1.3641 d-1 ,1.8783 d-1 , 1.4742 d-1 and 1.3209 d-1). Three of the frequencies are classified as l, m = (1, 1) pulsations and the other is ambiguous between l = 2 modes. Two frequencies are shown to be stable over twenty years since their first identification. The agreement in ground-based work makes this star an excellent calibrator for the upcoming TESS observations and a standard for continued asteroseismic modelling., Comment: Accepted for Publication in Monthly Notices of the Royal Astronomical Society, Volume 475, Issue 3, p.3813-3822
Published: 2018
Full Text: View/download PDF

9. The First Planetary Microlensing Event with Two Microlensed Source Stars

Author: Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. M., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Depoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. M., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Depoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Published: 2018

10. The First Planetary Microlensing Event with Two Microlensed Source Stars

Author: Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. K., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. K., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We present the analysis of microlensing event MOA-2010-BLG-117, and show that the light curve can only be explained by the gravitational lensing of a binary source star system by a star with a Jupiter mass ratio planet. It was necessary to modify standard microlensing modeling methods to find the correct light curve solution for this binary-source, binary-lens event. We are able to measure a strong microlensing parallax signal, which yields the masses of the host star, $M_* = 0.58\pm 0.11 M_\odot$, and planet $m_p = 0.54\pm 0.10 M_{\rm Jup}$ at a projected star-planet separation of $a_\perp = 2.42\pm 0.26\,$AU, corresponding to a semi-major axis of $a = 2.9{+1.6\atop -0.6}\,$AU. Thus, the system resembles a half-scale model of the Sun-Jupiter system with a half-Jupiter mass planet orbiting a half-solar mass star at very roughly half of Jupiter's orbital distance from the Sun. The source stars are slightly evolved, and by requiring them to lie on the same isochrone, we can constrain the source to lie in the near side of the bulge at a distance of $D_S = 6.9 \pm 0.7\,$kpc, which implies a distance to the planetary lens system of $D_L = 3.5\pm 0.4\,$kpc. The ability to model unusual planetary microlensing events, like this one, will be necessary to extract precise statistical information from the planned large exoplanet microlensing surveys, such as the WFIRST microlensing survey., Comment: Accepted version. Now published in AJ
Published: 2017
Full Text: View/download PDF

11. The First Planetary Microlensing Event with Two Microlensed Source Stars

Author: Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. K., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Udalski, A., Han, C., Bond, I. A., Beaulieu, J. -P., Skowron, J., Gaudi, B. S., Koshimoto, N., Abe, F., Asakura, Y., Barry, R. K., Bhattacharya, A., Donachie, M., Evans, P., Fukui, A., Hirao, Y., Itow, Y., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Ranc, C., Rattenbury, N. J., Rosenthal, M. K., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Szymanski, M. K., Poleski, R., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., DePoy, D., Gould, A., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Bowens-Rubin, R., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Horne, K., Hundertmark, M., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We present the analysis of microlensing event MOA-2010-BLG-117, and show that the light curve can only be explained by the gravitational lensing of a binary source star system by a star with a Jupiter mass ratio planet. It was necessary to modify standard microlensing modeling methods to find the correct light curve solution for this binary-source, binary-lens event. We are able to measure a strong microlensing parallax signal, which yields the masses of the host star, $M_* = 0.58\pm 0.11 M_\odot$, and planet $m_p = 0.54\pm 0.10 M_{\rm Jup}$ at a projected star-planet separation of $a_\perp = 2.42\pm 0.26\,$AU, corresponding to a semi-major axis of $a = 2.9{+1.6\atop -0.6}\,$AU. Thus, the system resembles a half-scale model of the Sun-Jupiter system with a half-Jupiter mass planet orbiting a half-solar mass star at very roughly half of Jupiter's orbital distance from the Sun. The source stars are slightly evolved, and by requiring them to lie on the same isochrone, we can constrain the source to lie in the near side of the bulge at a distance of $D_S = 6.9 \pm 0.7\,$kpc, which implies a distance to the planetary lens system of $D_L = 3.5\pm 0.4\,$kpc. The ability to model unusual planetary microlensing events, like this one, will be necessary to extract precise statistical information from the planned large exoplanet microlensing surveys, such as the WFIRST microlensing survey., Comment: Accepted version. Now published in AJ
Published: 2017
Full Text: View/download PDF

12. The First Circumbinary Planet Found by Microlensing: OGLE-2007-BLG-349L(AB)c

Author: Bennett, D. P., Rhie, S. H., Udalski, A., Gould, A., Tsapras, Y., Kubas, D., Bond, I. A., Greenhill, J., Cassan, A., Rattenbury, N. J., Boyajian, T. S., Luhn, J., Penny, M. T., Anderson, J., Abe, F., Bhattacharya, A., Botzler, C. S., Donachie, M., Freeman, M., Fukui, A., Hirao, Y., Itow, Y., Koshimoto, N., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Perrott, Y. C., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Yock, P. C. M., Szymanski, M. K., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Allen, W., DePoy, D., Gal-Yam, A., Gaudi, B. S., Han, C., Monard, I. A. G., Ofek, E., Pogge, R. W., Street, R. A., Bramich, D. M., Dominik, M., Horne, K., Snodgrass, C., Steele, I. A., Albrow, M. D., Bachelet, E., Batista, V., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hundertmark, M., Jorgensen, U. G., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Rhie, S. H., Udalski, A., Gould, A., Tsapras, Y., Kubas, D., Bond, I. A., Greenhill, J., Cassan, A., Rattenbury, N. J., Boyajian, T. S., Luhn, J., Penny, M. T., Anderson, J., Abe, F., Bhattacharya, A., Botzler, C. S., Donachie, M., Freeman, M., Fukui, A., Hirao, Y., Itow, Y., Koshimoto, N., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Perrott, Y. C., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Yock, P. C. M., Szymanski, M. K., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Allen, W., DePoy, D., Gal-Yam, A., Gaudi, B. S., Han, C., Monard, I. A. G., Ofek, E., Pogge, R. W., Street, R. A., Bramich, D. M., Dominik, M., Horne, K., Snodgrass, C., Steele, I. A., Albrow, M. D., Bachelet, E., Batista, V., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hundertmark, M., Jorgensen, U. G., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We present the analysis of the first circumbinary planet microlensing event, OGLE-2007-BLG-349. This event has a strong planetary signal that is best fit with a mass ratio of $q \approx 3.4\times10^{-4}$, but there is an additional signal due to an additional lens mass, either another planet or another star. We find acceptable light curve fits with two classes of models: 2-planet models (with a single host star) and circumbinary planet models. The light curve also reveals a significant microlensing parallax effect, which constrains the mass of the lens system to be $M_L \approx 0.7 M_\odot$. Hubble Space Telescope images resolve the lens and source stars from their neighbors and indicate excess flux due to the star(s) in the lens system. This is consistent with the predicted flux from the circumbinary models, where the lens mass is shared between two stars, but there is not enough flux to be consistent with the 2-planet, 1-star models. So, only the circumbinary models are consistent with the HST data. They indicate a planet of mass $m_c = 80\pm 13\,M_\oplus$, orbiting a pair of M-dwarfs with masses of $M_A = 0.41\pm 0.07 M_\odot$ and $M_B = 0.30\pm 0.07 M_\oplus$, which makes this the lowest mass circumbinary planet system known. The ratio of the separation between the planet and the center-of-mass to the separations of the two stars is $\sim 40$, so unlike most of the circumbinary planets found by Kepler, the planet does not orbit near the stability limit., Comment: 34 pages, with 9 figures. Published in the Astronomical Journal
Published: 2016
Full Text: View/download PDF

13. Spectroscopic Survey of {\gamma} Doradus Stars I. Comprehensive atmospheric parameters and abundance analysis of {\gamma} Doradus stars

Author: Kahraman-Alicavus, F., Niemczura, E., De Cat, P., Soydugan, E., Kolaczkowski, Z., Ostrowski, J., Telting, J. H., Uytterhoeven, K., Poretti, E., Rainer, M., Suarez, J. C., Mantegazza, L., Kilmartin, P., Pollard, K. R., Kahraman-Alicavus, F., Niemczura, E., De Cat, P., Soydugan, E., Kolaczkowski, Z., Ostrowski, J., Telting, J. H., Uytterhoeven, K., Poretti, E., Rainer, M., Suarez, J. C., Mantegazza, L., Kilmartin, P., and Pollard, K. R.
Abstract: We present a spectroscopic survey of known and candidate $\gamma$\,Doradus stars. The high-resolution, high signal-to-noise spectra of 52 objects were collected by five different spectrographs. The spectral classification, atmospheric parameters (\teff, $\log g$, $\xi$), $v\sin i$ and chemical composition of the stars were derived. The stellar spectral and luminosity classes were found between G0-A7 and IV-V, respectively. The initial values for \teff\ and \logg\ were determined from the photometric indices and spectral energy distribution. Those parameters were improved by the analysis of hydrogen lines. The final values of \teff, \logg\ and $\xi$ were derived from the iron lines analysis. The \teff\ values were found between 6000\,K and 7900\,K, while \logg\,values range from 3.8 to 4.5\,dex. Chemical abundances and $v\sin i$ values were derived by the spectrum synthesis method. The $v\sin i$ values were found between 5 and 240\,km\,s$^{-1}$. The chemical abundance pattern of $\gamma$\,Doradus stars were compared with the pattern of non-pulsating stars. It turned out that there is no significant difference in abundance patterns between these two groups. Additionally, the relations between the atmospheric parameters and the pulsation quantities were checked. A strong correlation between the $v\sin i$ and the pulsation periods of $\gamma$\,Doradus variables was obtained. The accurate positions of the analysed stars in the H-R diagram have been shown. Most of our objects are located inside or close to the blue edge of the theoretical instability strip of $\gamma$\,Doradus., Comment: 18 pages, 13 figures
Published: 2016
Full Text: View/download PDF

14. He II $\lambda$4686 emission from the massive binary system in $\eta$ Car: constraints to the orbital elements and the nature of the periodic minima

Author: Teodoro, M., Damineli, A., Heathcote, B., Richardson, N. D., Moffat, A. F. J., St-Jean, L., Russell, C., Gull, T. R., Madura, T. I., Pollard, K. R., Walter, F., Coimbra, A., Prates, R., Fernández-Lajús, E., Gamen, R. C., Hickel, G., Henrique, W., Navarete, F., Andrade, T., Jablonski, F., Luckas, P., Locke, M., Powles, J., Bohlsen, T., Chini, R., Corcoran, M. F., Hamaguchi, K., Groh, J. H., Hillier, D. J., Weigelt, G., Teodoro, M., Damineli, A., Heathcote, B., Richardson, N. D., Moffat, A. F. J., St-Jean, L., Russell, C., Gull, T. R., Madura, T. I., Pollard, K. R., Walter, F., Coimbra, A., Prates, R., Fernández-Lajús, E., Gamen, R. C., Hickel, G., Henrique, W., Navarete, F., Andrade, T., Jablonski, F., Luckas, P., Locke, M., Powles, J., Bohlsen, T., Chini, R., Corcoran, M. F., Hamaguchi, K., Groh, J. H., Hillier, D. J., and Weigelt, G.
Abstract: {\eta} Carinae is an extremely massive binary system in which rapid spectrum variations occur near periastron. Most notably, near periastron the He II $\lambda 4686$ line increases rapidly in strength, drops to a minimum value, then increases briefly before fading away. To understand this behavior, we conducted an intense spectroscopic monitoring of the He II $\lambda 4686$ emission line across the 2014.6 periastron passage using ground- and space-based telescopes. Comparison with previous data confirmed the overall repeatability of EW(He II $\lambda 4686$), the line radial velocities, and the timing of the minimum, though the strongest peak was systematically larger in 2014 than in 2009 by 26%. The EW(He II $\lambda 4686$) variations, combined with other measurements, yield an orbital period $2022.7\pm0.3$ d. The observed variability of the EW(He II $\lambda 4686$) was reproduced by a model in which the line flux primarily arises at the apex of the wind-wind collision and scales inversely with the square of the stellar separation, if we account for the excess emission as the companion star plunges into the hot inner layers of the primary's atmosphere, and including absorption from the disturbed primary wind between the source and the observer. This model constrains the orbital inclination to $135^\circ$-$153^\circ$, and the longitude of periastron to $234^\circ$-$252^\circ$. It also suggests that periastron passage occurred on $T_0 = 2456874.4\pm1.3$ d. Our model also reproduced EW(He II $\lambda 4686$) variations from a polar view of the primary star as determined from the observed He II $\lambda 4686$ emission scattered off the Homunculus nebula., Comment: The article contains 23 pages and 17 figures. It has been accepted for publication in ApJ
Published: 2016
Full Text: View/download PDF

15. The First Circumbinary Planet Found by Microlensing: OGLE-2007-BLG-349L(AB)c

Author: Bennett, D. P., Rhie, S. H., Udalski, A., Gould, A., Tsapras, Y., Kubas, D., Bond, I. A., Greenhill, J., Cassan, A., Rattenbury, N. J., Boyajian, T. S., Luhn, J., Penny, M. T., Anderson, J., Abe, F., Bhattacharya, A., Botzler, C. S., Donachie, M., Freeman, M., Fukui, A., Hirao, Y., Itow, Y., Koshimoto, N., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Perrott, Y. C., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Yock, P. C. M., Szymanski, M. K., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Allen, W., DePoy, D., Gal-Yam, A., Gaudi, B. S., Han, C., Monard, I. A. G., Ofek, E., Pogge, R. W., Street, R. A., Bramich, D. M., Dominik, M., Horne, K., Snodgrass, C., Steele, I. A., Albrow, M. D., Bachelet, E., Batista, V., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hundertmark, M., Jorgensen, U. G., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Bennett, D. P., Rhie, S. H., Udalski, A., Gould, A., Tsapras, Y., Kubas, D., Bond, I. A., Greenhill, J., Cassan, A., Rattenbury, N. J., Boyajian, T. S., Luhn, J., Penny, M. T., Anderson, J., Abe, F., Bhattacharya, A., Botzler, C. S., Donachie, M., Freeman, M., Fukui, A., Hirao, Y., Itow, Y., Koshimoto, N., Li, M. C. A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagakane, M., Ohnishi, K., Oyokawa, H., Perrott, Y. C., Saito, To., Sharan, A., Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Yonehara, A., Yock, P. C. M., Szymanski, M. K., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Allen, W., DePoy, D., Gal-Yam, A., Gaudi, B. S., Han, C., Monard, I. A. G., Ofek, E., Pogge, R. W., Street, R. A., Bramich, D. M., Dominik, M., Horne, K., Snodgrass, C., Steele, I. A., Albrow, M. D., Bachelet, E., Batista, V., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hundertmark, M., Jorgensen, U. G., Kains, N., Kane, S. R., Marquette, J. -B., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We present the analysis of the first circumbinary planet microlensing event, OGLE-2007-BLG-349. This event has a strong planetary signal that is best fit with a mass ratio of $q \approx 3.4\times10^{-4}$, but there is an additional signal due to an additional lens mass, either another planet or another star. We find acceptable light curve fits with two classes of models: 2-planet models (with a single host star) and circumbinary planet models. The light curve also reveals a significant microlensing parallax effect, which constrains the mass of the lens system to be $M_L \approx 0.7 M_\odot$. Hubble Space Telescope images resolve the lens and source stars from their neighbors and indicate excess flux due to the star(s) in the lens system. This is consistent with the predicted flux from the circumbinary models, where the lens mass is shared between two stars, but there is not enough flux to be consistent with the 2-planet, 1-star models. So, only the circumbinary models are consistent with the HST data. They indicate a planet of mass $m_c = 80\pm 13\,M_\oplus$, orbiting a pair of M-dwarfs with masses of $M_A = 0.41\pm 0.07 M_\odot$ and $M_B = 0.30\pm 0.07 M_\oplus$, which makes this the lowest mass circumbinary planet system known. The ratio of the separation between the planet and the center-of-mass to the separations of the two stars is $\sim 40$, so unlike most of the circumbinary planets found by Kepler, the planet does not orbit near the stability limit., Comment: 34 pages, with 9 figures. Published in the Astronomical Journal
Published: 2016
Full Text: View/download PDF

16. Spectroscopic Survey of {\gamma} Doradus Stars I. Comprehensive atmospheric parameters and abundance analysis of {\gamma} Doradus stars

Author: Kahraman-Alicavus, F., Niemczura, E., De Cat, P., Soydugan, E., Kolaczkowski, Z., Ostrowski, J., Telting, J. H., Uytterhoeven, K., Poretti, E., Rainer, M., Suarez, J. C., Mantegazza, L., Kilmartin, P., Pollard, K. R., Kahraman-Alicavus, F., Niemczura, E., De Cat, P., Soydugan, E., Kolaczkowski, Z., Ostrowski, J., Telting, J. H., Uytterhoeven, K., Poretti, E., Rainer, M., Suarez, J. C., Mantegazza, L., Kilmartin, P., and Pollard, K. R.
Abstract: We present a spectroscopic survey of known and candidate $\gamma$\,Doradus stars. The high-resolution, high signal-to-noise spectra of 52 objects were collected by five different spectrographs. The spectral classification, atmospheric parameters (\teff, $\log g$, $\xi$), $v\sin i$ and chemical composition of the stars were derived. The stellar spectral and luminosity classes were found between G0-A7 and IV-V, respectively. The initial values for \teff\ and \logg\ were determined from the photometric indices and spectral energy distribution. Those parameters were improved by the analysis of hydrogen lines. The final values of \teff, \logg\ and $\xi$ were derived from the iron lines analysis. The \teff\ values were found between 6000\,K and 7900\,K, while \logg\,values range from 3.8 to 4.5\,dex. Chemical abundances and $v\sin i$ values were derived by the spectrum synthesis method. The $v\sin i$ values were found between 5 and 240\,km\,s$^{-1}$. The chemical abundance pattern of $\gamma$\,Doradus stars were compared with the pattern of non-pulsating stars. It turned out that there is no significant difference in abundance patterns between these two groups. Additionally, the relations between the atmospheric parameters and the pulsation quantities were checked. A strong correlation between the $v\sin i$ and the pulsation periods of $\gamma$\,Doradus variables was obtained. The accurate positions of the analysed stars in the H-R diagram have been shown. Most of our objects are located inside or close to the blue edge of the theoretical instability strip of $\gamma$\,Doradus., Comment: 18 pages, 13 figures
Published: 2016
Full Text: View/download PDF

17. He II $\lambda$4686 emission from the massive binary system in $\eta$ Car: constraints to the orbital elements and the nature of the periodic minima

Author: Teodoro, M., Damineli, A., Heathcote, B., Richardson, N. D., Moffat, A. F. J., St-Jean, L., Russell, C., Gull, T. R., Madura, T. I., Pollard, K. R., Walter, F., Coimbra, A., Prates, R., Fernández-Lajús, E., Gamen, R. C., Hickel, G., Henrique, W., Navarete, F., Andrade, T., Jablonski, F., Luckas, P., Locke, M., Powles, J., Bohlsen, T., Chini, R., Corcoran, M. F., Hamaguchi, K., Groh, J. H., Hillier, D. J., Weigelt, G., Teodoro, M., Damineli, A., Heathcote, B., Richardson, N. D., Moffat, A. F. J., St-Jean, L., Russell, C., Gull, T. R., Madura, T. I., Pollard, K. R., Walter, F., Coimbra, A., Prates, R., Fernández-Lajús, E., Gamen, R. C., Hickel, G., Henrique, W., Navarete, F., Andrade, T., Jablonski, F., Luckas, P., Locke, M., Powles, J., Bohlsen, T., Chini, R., Corcoran, M. F., Hamaguchi, K., Groh, J. H., Hillier, D. J., and Weigelt, G.
Abstract: {\eta} Carinae is an extremely massive binary system in which rapid spectrum variations occur near periastron. Most notably, near periastron the He II $\lambda 4686$ line increases rapidly in strength, drops to a minimum value, then increases briefly before fading away. To understand this behavior, we conducted an intense spectroscopic monitoring of the He II $\lambda 4686$ emission line across the 2014.6 periastron passage using ground- and space-based telescopes. Comparison with previous data confirmed the overall repeatability of EW(He II $\lambda 4686$), the line radial velocities, and the timing of the minimum, though the strongest peak was systematically larger in 2014 than in 2009 by 26%. The EW(He II $\lambda 4686$) variations, combined with other measurements, yield an orbital period $2022.7\pm0.3$ d. The observed variability of the EW(He II $\lambda 4686$) was reproduced by a model in which the line flux primarily arises at the apex of the wind-wind collision and scales inversely with the square of the stellar separation, if we account for the excess emission as the companion star plunges into the hot inner layers of the primary's atmosphere, and including absorption from the disturbed primary wind between the source and the observer. This model constrains the orbital inclination to $135^\circ$-$153^\circ$, and the longitude of periastron to $234^\circ$-$252^\circ$. It also suggests that periastron passage occurred on $T_0 = 2456874.4\pm1.3$ d. Our model also reproduced EW(He II $\lambda 4686$) variations from a polar view of the primary star as determined from the observed He II $\lambda 4686$ emission scattered off the Homunculus nebula., Comment: The article contains 23 pages and 17 figures. It has been accepted for publication in ApJ
Published: 2016
Full Text: View/download PDF

18. MOA-2007-BLG-197: Exploring the brown dwarf desert

Author: Ranc, C., Cassan, A., Albrow, M. D., Kubas, D., Bond, I. A., Batista, V., Beaulieu, J. -P., Bennett, D. P., Dominik, M., Dong, Subo, Fouqué, P., Gould, A., Greenhill, J., Jørgensen, U. G., Kains, N., Menzies, J., Sumi, T., Bachelet, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Gaudi, B. S., Han, C., Hundertmark, M., Horne, K., Kane, S. R., Lee, C. -U., Marquette, J. -B., Park, B. -G., Pollard, K. R., Sahu, K. C., Street, R., Tsapras, Y., Wambsganss, J., Williams, A., Zub, M., Abe, F., Fukui, A., Itow, Y., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Yonehara, A., Ranc, C., Cassan, A., Albrow, M. D., Kubas, D., Bond, I. A., Batista, V., Beaulieu, J. -P., Bennett, D. P., Dominik, M., Dong, Subo, Fouqué, P., Gould, A., Greenhill, J., Jørgensen, U. G., Kains, N., Menzies, J., Sumi, T., Bachelet, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Gaudi, B. S., Han, C., Hundertmark, M., Horne, K., Kane, S. R., Lee, C. -U., Marquette, J. -B., Park, B. -G., Pollard, K. R., Sahu, K. C., Street, R., Tsapras, Y., Wambsganss, J., Williams, A., Zub, M., Abe, F., Fukui, A., Itow, Y., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., and Yonehara, A.
Abstract: We present the analysis of MOA-2007-BLG-197Lb, the first brown dwarf companion to a Sun-like star detected through gravitational microlensing. The event was alerted and followed-up photometrically by a network of telescopes from the PLANET, MOA, and uFUN collaborations, and observed at high angular resolution using the NaCo instrument at the VLT. From the modelling of the microlensing light curve, we derived the binary lens separation in Einstein radius units (s~1.13) and a mass ratio of (4.732+/-0.020)x10^{-2}. Annual parallax, lens orbital motion and finite source effects were included in the models. To recover the lens system's physical parameters, we combined the resulting light curve best-fit parameters with (J,H,Ks) magnitudes obtained with VLT NaCo and calibrated using IRSF and 2MASS data. We derived a lens total mass of 0.86+/-0.04 Msun and a lens distance of 4.2+/-0.3 kpc. We find that the companion of MOA-2007-BLG-197L is a brown dwarf of 41+/-2 Mjup observed at a projected separation of 4.3+/-0.1 AU, and orbits a 0.82+/-0.04 Msun G-K dwarf star. We study the statistical properties of this population of brown dwarfs detected by microlensing, transit, radial velocity, and direct imaging (most of these objects orbit solar-type stars), and we performed a two-dimensional, non-parametric probability density distribution fit to the data, which draws a structured brown dwarf landscape. We confirm the existence of a region that is strongly depleted in objects at short periods and intermediate masses (P<30 d, M~30-60 Mjup), but also find an accumulation of objects around P~500 d and M~20 Mjup, as well as another depletion region at long orbital periods (P>500 d) and high masses (M>50 Mjup). While these data provide important clues on mechanisms of brown dwarfs formation, more data are needed to establish their relative importance, in particular as a function of host star mass., Comment: 16 pages, 12 figures
Published: 2015
Full Text: View/download PDF

19. MOA-2007-BLG-197: Exploring the brown dwarf desert

Author: Ranc, C., Cassan, A., Albrow, M. D., Kubas, D., Bond, I. A., Batista, V., Beaulieu, J. -P., Bennett, D. P., Dominik, M., Dong, Subo, Fouqué, P., Gould, A., Greenhill, J., Jørgensen, U. G., Kains, N., Menzies, J., Sumi, T., Bachelet, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Gaudi, B. S., Han, C., Hundertmark, M., Horne, K., Kane, S. R., Lee, C. -U., Marquette, J. -B., Park, B. -G., Pollard, K. R., Sahu, K. C., Street, R., Tsapras, Y., Wambsganss, J., Williams, A., Zub, M., Abe, F., Fukui, A., Itow, Y., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Yonehara, A., Ranc, C., Cassan, A., Albrow, M. D., Kubas, D., Bond, I. A., Batista, V., Beaulieu, J. -P., Bennett, D. P., Dominik, M., Dong, Subo, Fouqué, P., Gould, A., Greenhill, J., Jørgensen, U. G., Kains, N., Menzies, J., Sumi, T., Bachelet, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Gaudi, B. S., Han, C., Hundertmark, M., Horne, K., Kane, S. R., Lee, C. -U., Marquette, J. -B., Park, B. -G., Pollard, K. R., Sahu, K. C., Street, R., Tsapras, Y., Wambsganss, J., Williams, A., Zub, M., Abe, F., Fukui, A., Itow, Y., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., and Yonehara, A.
Abstract: We present the analysis of MOA-2007-BLG-197Lb, the first brown dwarf companion to a Sun-like star detected through gravitational microlensing. The event was alerted and followed-up photometrically by a network of telescopes from the PLANET, MOA, and uFUN collaborations, and observed at high angular resolution using the NaCo instrument at the VLT. From the modelling of the microlensing light curve, we derived the binary lens separation in Einstein radius units (s~1.13) and a mass ratio of (4.732+/-0.020)x10^{-2}. Annual parallax, lens orbital motion and finite source effects were included in the models. To recover the lens system's physical parameters, we combined the resulting light curve best-fit parameters with (J,H,Ks) magnitudes obtained with VLT NaCo and calibrated using IRSF and 2MASS data. We derived a lens total mass of 0.86+/-0.04 Msun and a lens distance of 4.2+/-0.3 kpc. We find that the companion of MOA-2007-BLG-197L is a brown dwarf of 41+/-2 Mjup observed at a projected separation of 4.3+/-0.1 AU, and orbits a 0.82+/-0.04 Msun G-K dwarf star. We study the statistical properties of this population of brown dwarfs detected by microlensing, transit, radial velocity, and direct imaging (most of these objects orbit solar-type stars), and we performed a two-dimensional, non-parametric probability density distribution fit to the data, which draws a structured brown dwarf landscape. We confirm the existence of a region that is strongly depleted in objects at short periods and intermediate masses (P<30 d, M~30-60 Mjup), but also find an accumulation of objects around P~500 d and M~20 Mjup, as well as another depletion region at long orbital periods (P>500 d) and high masses (M>50 Mjup). While these data provide important clues on mechanisms of brown dwarfs formation, more data are needed to establish their relative importance, in particular as a function of host star mass., Comment: 16 pages, 12 figures
Published: 2015
Full Text: View/download PDF

20. OGLE-2011-BLG-0265Lb: A JOVIAN MICROLENSING PLANET ORBITING AN M DWARF

Author: Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Prester, D. Dominis, Street, R. A., Jorgensen, U. G., Bennett, D. P., Bozza, V., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedmann, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., Depoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, C. H., Dieters, S., Donatowicz, J., Fouque, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Prester, D. Dominis, Street, R. A., Jorgensen, U. G., Bennett, D. P., Bozza, V., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedmann, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., Depoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J. C., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, C. H., Dieters, S., Donatowicz, J., Fouque, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., and Wertz, O.
Published: 2015

21. OGLE-2011-BLG-0265Lb: a Jovian Microlensing Planet Orbiting an M Dwarf

Author: Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Dominis-Prester, D., Street, R. A., Jørgensen, U. G., Bennett, D. P., Bozza, V., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedman, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., DePoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Donatowicz, J., Fouqué, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Dominis-Prester, D., Street, R. A., Jørgensen, U. G., Bennett, D. P., Bozza, V., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedman, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., DePoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Donatowicz, J., Fouqué, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., and Wertz, O.
Abstract: We report the discovery of a Jupiter-mass planet orbiting an M-dwarf star that gave rise to the microlensing event OGLE-2011-BLG-0265. Such a system is very rare among known planetary systems and thus the discovery is important for theoretical studies of planetary formation and evolution. High-cadence temporal coverage of the planetary signal combined with extended observations throughout the event allows us to accurately model the observed light curve. The final microlensing solution remains, however, degenerate yielding two possible configurations of the planet and the host star. In the case of the preferred solution, the mass of the planet is $M_{\rm p} = 0.9\pm 0.3\ M_{\rm J}$, and the planet is orbiting a star with a mass $M = 0.22\pm 0.06\ M_\odot$. The second possible configuration (2$\sigma$ away) consists of a planet with $M_{\rm p}=0.6\pm 0.3\ M_{\rm J}$ and host star with $M=0.14\pm 0.06\ M_\odot$. The system is located in the Galactic disk 3 -- 4 kpc towards the Galactic bulge. In both cases, with an orbit size of 1.5 -- 2.0 AU, the planet is a "cold Jupiter" -- located well beyond the "snow line" of the host star. Currently available data make the secure selection of the correct solution difficult, but there are prospects for lifting the degeneracy with additional follow-up observations in the future, when the lens and source star separate., Comment: 10 pages, 2 tables, 5 figures. Accepted in ApJ
Published: 2014
Full Text: View/download PDF

22. The classification of frequencies in the {\gamma} Doradus / {\delta} Scuti hybrid star HD 49434

Author: Brunsden, E., Pollard, K. R., Cottrell, P. L., Uytterhoeven, K., Wright, D. J., De Cat, P., Brunsden, E., Pollard, K. R., Cottrell, P. L., Uytterhoeven, K., Wright, D. J., and De Cat, P.
Abstract: Hybrid stars of the {\gamma} Doradus and {\delta} Scuti pulsation types have great potential for asteroseismic analysis to explore their interior structure. To achieve this, mode identi- fications of pulsational frequencies observed in the stars must be made, a task which is far from simple. In this work we begin the analysis by scrutinizing the frequencies found in the CoRoT photometric satellite measurements and ground-based high-resolution spectroscopy of the hybrid star HD 49434. The results show almost no consistency between the frequencies found using the two techniques and no characteristic period spacings or couplings were identified in either dataset. The spectroscopic data additionally show no evidence for any long term (5 year) variation in the dominant frequency. The 31 spectroscopic frequencies identified have standard deviation profiles suggesting multiple modes sharing (l, m) in the {\delta} Scuti frequency region and several skewed modes sharing the same (l, m) in the {\gamma} Doradus frequency region. In addition, there is a clear frequency in the {\gamma} Doradus frequency region that appears to be unrelated to the others. We conclude HD 49434 remains a {\delta} Scuti/ {\gamma} Doradus candidate hybrid star but more sophisticated models dealing with rotation are sought to obtain a clear picture of the pulsational behaviour of this star., Comment: Accepted for publication in MNRAS December 2014
Published: 2014
Full Text: View/download PDF

23. The classification of frequencies in the {\gamma} Doradus / {\delta} Scuti hybrid star HD 49434

Author: Brunsden, E., Pollard, K. R., Cottrell, P. L., Uytterhoeven, K., Wright, D. J., De Cat, P., Brunsden, E., Pollard, K. R., Cottrell, P. L., Uytterhoeven, K., Wright, D. J., and De Cat, P.
Abstract: Hybrid stars of the {\gamma} Doradus and {\delta} Scuti pulsation types have great potential for asteroseismic analysis to explore their interior structure. To achieve this, mode identi- fications of pulsational frequencies observed in the stars must be made, a task which is far from simple. In this work we begin the analysis by scrutinizing the frequencies found in the CoRoT photometric satellite measurements and ground-based high-resolution spectroscopy of the hybrid star HD 49434. The results show almost no consistency between the frequencies found using the two techniques and no characteristic period spacings or couplings were identified in either dataset. The spectroscopic data additionally show no evidence for any long term (5 year) variation in the dominant frequency. The 31 spectroscopic frequencies identified have standard deviation profiles suggesting multiple modes sharing (l, m) in the {\delta} Scuti frequency region and several skewed modes sharing the same (l, m) in the {\gamma} Doradus frequency region. In addition, there is a clear frequency in the {\gamma} Doradus frequency region that appears to be unrelated to the others. We conclude HD 49434 remains a {\delta} Scuti/ {\gamma} Doradus candidate hybrid star but more sophisticated models dealing with rotation are sought to obtain a clear picture of the pulsational behaviour of this star., Comment: Accepted for publication in MNRAS December 2014
Published: 2014
Full Text: View/download PDF

24. OGLE-2011-BLG-0265Lb: a Jovian Microlensing Planet Orbiting an M Dwarf

Author: Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Dominis-Prester, D., Street, R. A., Jørgensen, U. G., Bennett, D. P., Bozza, V., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedman, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., DePoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Donatowicz, J., Fouqué, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Skowron, J., Shin, I. -G., Udalski, A., Han, C., Sumi, T., Shvartzvald, Y., Gould, A., Dominis-Prester, D., Street, R. A., Jørgensen, U. G., Bennett, D. P., Bozza, V., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Abe, F., Bhattacharya, A., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Suzuki, D., Tristram, P. J., Yock, P. C. M., Maoz, D., Kaspi, S., Friedman, M., Almeida, L. A., Batista, V., Christie, G., Choi, J. -Y., DePoy, D. L., Gaudi, B. S., Henderson, C., Hwang, K. -H., Jablonski, F., Jung, Y. K., Lee, C. -U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Donatowicz, J., Fouqué, P., Greenhill, J., Kains, N., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Ranc, C., Sahu, K. C., Wambsganss, J., Williams, A., Wouters, D., Tsapras, Y., Bramich, D. M., Horne, K., Hundertmark, M., Snodgrass, C., Steele, I. A., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Gu, C. -H., Hardis, Harpsøe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., and Wertz, O.
Abstract: We report the discovery of a Jupiter-mass planet orbiting an M-dwarf star that gave rise to the microlensing event OGLE-2011-BLG-0265. Such a system is very rare among known planetary systems and thus the discovery is important for theoretical studies of planetary formation and evolution. High-cadence temporal coverage of the planetary signal combined with extended observations throughout the event allows us to accurately model the observed light curve. The final microlensing solution remains, however, degenerate yielding two possible configurations of the planet and the host star. In the case of the preferred solution, the mass of the planet is $M_{\rm p} = 0.9\pm 0.3\ M_{\rm J}$, and the planet is orbiting a star with a mass $M = 0.22\pm 0.06\ M_\odot$. The second possible configuration (2$\sigma$ away) consists of a planet with $M_{\rm p}=0.6\pm 0.3\ M_{\rm J}$ and host star with $M=0.14\pm 0.06\ M_\odot$. The system is located in the Galactic disk 3 -- 4 kpc towards the Galactic bulge. In both cases, with an orbit size of 1.5 -- 2.0 AU, the planet is a "cold Jupiter" -- located well beyond the "snow line" of the host star. Currently available data make the secure selection of the correct solution difficult, but there are prospects for lifting the degeneracy with additional follow-up observations in the future, when the lens and source star separate., Comment: 10 pages, 2 tables, 5 figures. Accepted in ApJ
Published: 2014
Full Text: View/download PDF

25. A SUPER-JUPITER ORBITING A LATE-TYPE STAR:A REFINED ANALYSIS OF MICROLENSING EVENT OGLE-2012-BLG-0406

Author: Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jorgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, Markus Peter Gerhard, Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, Kennet Bomann West, Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozllowski, S., Wyrzykowski, E., Szymanski, M. K., Kubiak, M., Pietrukowicz, P., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., Ere, C. P., Pollard, K. R., Zub, M., Christie, G., Depoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jorgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, Markus Peter Gerhard, Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, Kennet Bomann West, Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozllowski, S., Wyrzykowski, E., Szymanski, M. K., Kubiak, M., Pietrukowicz, P., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., Ere, C. P., Pollard, K. R., Zub, M., Christie, G., Depoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., and Yonehara, A.
Published: 2014

26. A SUPER-JUPITER ORBITING A LATE-TYPE STAR:A REFINED ANALYSIS OF MICROLENSING EVENT OGLE-2012-BLG-0406

Author: Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jorgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, Markus Peter Gerhard, Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, Kennet Bomann West, Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozllowski, S., Wyrzykowski, E., Szymanski, M. K., Kubiak, M., Pietrukowicz, P., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., Ere, C. P., Pollard, K. R., Zub, M., Christie, G., Depoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jorgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, Markus Peter Gerhard, Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, Kennet Bomann West, Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozllowski, S., Wyrzykowski, E., Szymanski, M. K., Kubiak, M., Pietrukowicz, P., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., Ere, C. P., Pollard, K. R., Zub, M., Christie, G., Depoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., and Yonehara, A.
Published: 2014

27. Extensive study of HD 25558, a long-period double-lined binary with two SPB components

Author: Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs., Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vučković, M., collaboration, the MiMeS, Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs., Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vučković, M., and collaboration, the MiMeS
Abstract: We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ~2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about 9 years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. Eleven independent frequencies were identified in the data. All the frequencies were attributed to one of the two components based on Pixel-by-pixel variability analysis of the line profiles. Spectroscopic and photometric mode identification was also performed for the frequencies of both stars. These results suggest that the inclination and rotation of the two components are rather different. The primary is a slow rotator with ~6 d period, seen at ~60 deg inclination, while the secondary rotates fast with ~1.2 d period, and is seen at ~20 inclination. Spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field can be detected in the primary., Comment: 24 pages, 12 figures, 11 tables. Accepted for publication in MNRAS
Published: 2013
Full Text: View/download PDF

28. A Super-Jupiter orbiting a late-type star: A refined analysis of microlensing event OGLE-2012-BLG-0406

Author: Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jørgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, K., Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozłowski, S., Wyrzykowski, Łukasz, Szymański, M. K., Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., P`ere, C., Pollard, K. R., Wouters, D., Christie, G., DePoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yonehara, P. C. M. Yock A., Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jørgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, K., Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozłowski, S., Wyrzykowski, Łukasz, Szymański, M. K., Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., P`ere, C., Pollard, K. R., Wouters, D., Christie, G., DePoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., and Yonehara, P. C. M. Yock A.
Abstract: We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve, especially the perturbation part, allowed us to accurately measure the parallax effect and lens orbital motion. Combining our measurement of the lens parallax with the angular Einstein radius determined from finite-source effects, we estimate the physical parameters of the lens system. We find that the event was caused by a $2.73\pm 0.43\ M_{\rm J}$ planet orbiting a $0.44\pm 0.07\ M_{\odot}$ early M-type star. The distance to the lens is $4.97\pm 0.29$\ kpc and the projected separation between the host star and its planet at the time of the event is $3.45\pm 0.26$ AU. We find that the additional coverage provided by follow-up observations, especially during the planetary perturbation, leads to a more accurate determination of the physical parameters of the lens., Comment: 9 pages, 4 figures, accepted by ApJ
Published: 2013
Full Text: View/download PDF

29. Interpretation of a Short-Term Anomaly in the Gravitational Microlensing Event MOA-2012-BLG-486

Author: Hwang, K. -H., Choi, J. -Y., Bond, I. A., Sumi, T., Han, C., Gaudi, B. S., Gould, A., Bozza, V., Beaulieu, J. -P., Tsapras, Y., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Fukunaga, D., Harris, P., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., de Almeida, L. Andrade, DePoy, D. L., Dong, Subo, Jablonski, F., Jung, Y. K., Kavka, A., Lee, C. -U., Park, H., Pogge, R. W., Shin, I. -G., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Jørgensen, U. G., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Bramich, D. M., Dominik, M., Horne, K., Browne, P., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Street, R. A., Hwang, K. -H., Choi, J. -Y., Bond, I. A., Sumi, T., Han, C., Gaudi, B. S., Gould, A., Bozza, V., Beaulieu, J. -P., Tsapras, Y., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Fukunaga, D., Harris, P., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., de Almeida, L. Andrade, DePoy, D. L., Dong, Subo, Jablonski, F., Jung, Y. K., Kavka, A., Lee, C. -U., Park, H., Pogge, R. W., Shin, I. -G., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Jørgensen, U. G., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Bramich, D. M., Dominik, M., Horne, K., Browne, P., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., and Street, R. A.
Abstract: A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals., Comment: 5 pages, 4 figures and ApJ submitted
Published: 2013
Full Text: View/download PDF

30. Gravitational Binary-lens Events with Prominent Effects of Lens Orbital Motion

Author: Park, H., Udalski, A., Han, C., Gould, A., Beaulieu, J. -P., Tsapras, Y., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Choi, J. -Y., Depoy, D. L., Dong, Subo, Gaudi, B. S., Hwang, K. -H., Jung, Y. K., Kavka, A., Lee, C. -U., Monard, L. A. G., Park, B. -G., Pogge, R. W., Porritt, I., Shin, I. -G., Yee, J. C., Albrow, M. D., Bennett, D. P., Caldwell, J. A. R., Cassan, A., Coutures, C., Dominis, D., Donatowicz, J., Fouqué, P., Greenhill, J., Huber, M., Jørgensen, U. G., Kane, S., Kubas, D., Marquette, J. -B., Menzies, J., Pitrou, C., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Allan, A., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Kains, N., Snodgrass, C., Steele, I. A., Street, R. A., Park, H., Udalski, A., Han, C., Gould, A., Beaulieu, J. -P., Tsapras, Y., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Choi, J. -Y., Depoy, D. L., Dong, Subo, Gaudi, B. S., Hwang, K. -H., Jung, Y. K., Kavka, A., Lee, C. -U., Monard, L. A. G., Park, B. -G., Pogge, R. W., Porritt, I., Shin, I. -G., Yee, J. C., Albrow, M. D., Bennett, D. P., Caldwell, J. A. R., Cassan, A., Coutures, C., Dominis, D., Donatowicz, J., Fouqué, P., Greenhill, J., Huber, M., Jørgensen, U. G., Kane, S., Kubas, D., Marquette, J. -B., Menzies, J., Pitrou, C., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Allan, A., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Kains, N., Snodgrass, C., Steele, I. A., and Street, R. A.
Abstract: Gravitational microlensing events produced by lenses composed of binary masses are important because they provide a major channel to determine physical parameters of lenses. In this work, we analyze the light curves of two binary-lens events OGLE-2006-BLG-277 and OGLE-2012-BLG-0031 for which the light curves exhibit strong deviations from standard models. From modeling considering various second-order effects, we find that the deviations are mostly explained by the effect of the lens orbital motion. We also find that lens parallax effects can mimic orbital effects to some extent. This implies that modeling light curves of binary-lens events not considering orbital effects can result in lens parallaxes that are substantially different from actual values and thus wrong determinations of physical lens parameters. This demonstrates the importance of routine consideration of orbital effects in interpreting light curves of binary-lens events. It is found that the lens of OGLE-2006-BLG-277 is a binary composed of a low-mass star and a brown dwarf companion., Comment: 6 pages and 4 figures
Published: 2013
Full Text: View/download PDF

31. A Giant Planet beyond the Snow Line in Microlensing Event OGLE-2011-BLG-0251

Author: Kains, N., Street, R., Choi, J. -Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P., Jorgensen, U. G., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsoe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S. -J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y. -K., Koo, J. -R., Lee, C. -U., McCormick, J., McGregor, D., Munoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I. -G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Zub, M., Kains, N., Street, R., Choi, J. -Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P., Jorgensen, U. G., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsoe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S. -J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y. -K., Koo, J. -R., Lee, C. -U., McCormick, J., McGregor, D., Munoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I. -G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., and Zub, M.
Abstract: We present the analysis of the gravitational microlensing event OGLE-2011-BLG-0251. This anomalous event was observed by several survey and follow-up collaborations conducting microlensing observations towards the Galactic Bulge. Based on detailed modelling of the observed light curve, we find that the lens is composed of two masses with a mass ratio q=1.9 x 10^-3. Thanks to our detection of higher-order effects on the light curve due to the Earth's orbital motion and the finite size of source, we are able to measure the mass and distance to the lens unambiguously. We find that the lens is made up of a planet of mass 0.53 +- 0.21,M_Jup orbiting an M dwarf host star with a mass of 0.26 +- 0.11 M_Sun. The planetary system is located at a distance of 2.57 +- 0.61 kpc towards the Galactic Centre. The projected separation of the planet from its host star is d=1.408 +- 0.019, in units of the Einstein radius, which corresponds to 2.72 +- 0.75 AU in physical units. We also identified a competitive model with similar planet and host star masses, but with a smaller orbital radius of 1.50 +- 0.50 AU. The planet is therefore located beyond the snow line of its host star, which we estimate to be around 1-1.5 AU., Comment: 12 pages, 7 figures, 3 tables; A&A in press
Published: 2013
Full Text: View/download PDF

32. A Giant Planet beyond the Snow Line in Microlensing Event OGLE-2011-BLG-0251

Author: Kains, N., Street, R., Choi, J. -Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P., Jorgensen, U. G., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsoe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S. -J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y. -K., Koo, J. -R., Lee, C. -U., McCormick, J., McGregor, D., Munoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I. -G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Zub, M., Kains, N., Street, R., Choi, J. -Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P., Jorgensen, U. G., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Kozlowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, L., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dominik, M., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsoe, K., Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S. -J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y. -K., Koo, J. -R., Lee, C. -U., McCormick, J., McGregor, D., Munoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I. -G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J. -P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., and Zub, M.
Abstract: We present the analysis of the gravitational microlensing event OGLE-2011-BLG-0251. This anomalous event was observed by several survey and follow-up collaborations conducting microlensing observations towards the Galactic Bulge. Based on detailed modelling of the observed light curve, we find that the lens is composed of two masses with a mass ratio q=1.9 x 10^-3. Thanks to our detection of higher-order effects on the light curve due to the Earth's orbital motion and the finite size of source, we are able to measure the mass and distance to the lens unambiguously. We find that the lens is made up of a planet of mass 0.53 +- 0.21,M_Jup orbiting an M dwarf host star with a mass of 0.26 +- 0.11 M_Sun. The planetary system is located at a distance of 2.57 +- 0.61 kpc towards the Galactic Centre. The projected separation of the planet from its host star is d=1.408 +- 0.019, in units of the Einstein radius, which corresponds to 2.72 +- 0.75 AU in physical units. We also identified a competitive model with similar planet and host star masses, but with a smaller orbital radius of 1.50 +- 0.50 AU. The planet is therefore located beyond the snow line of its host star, which we estimate to be around 1-1.5 AU., Comment: 12 pages, 7 figures, 3 tables; A&A in press
Published: 2013
Full Text: View/download PDF

33. Extensive study of HD 25558, a long-period double-lined binary with two SPB components

Author: Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs., Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vučković, M., collaboration, the MiMeS, Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs., Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vučković, M., and collaboration, the MiMeS
Abstract: We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ~2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about 9 years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. Eleven independent frequencies were identified in the data. All the frequencies were attributed to one of the two components based on Pixel-by-pixel variability analysis of the line profiles. Spectroscopic and photometric mode identification was also performed for the frequencies of both stars. These results suggest that the inclination and rotation of the two components are rather different. The primary is a slow rotator with ~6 d period, seen at ~60 deg inclination, while the secondary rotates fast with ~1.2 d period, and is seen at ~20 inclination. Spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field can be detected in the primary., Comment: 24 pages, 12 figures, 11 tables. Accepted for publication in MNRAS
Published: 2013
Full Text: View/download PDF

34. A Super-Jupiter orbiting a late-type star: A refined analysis of microlensing event OGLE-2012-BLG-0406

Author: Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jørgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, K., Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozłowski, S., Wyrzykowski, Łukasz, Szymański, M. K., Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., P`ere, C., Pollard, K. R., Wouters, D., Christie, G., DePoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yonehara, P. C. M. Yock A., Tsapras, Y., Choi, J. -Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J. -P., Udalski, A., Jørgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, K., Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozłowski, S., Wyrzykowski, Łukasz, Szymański, M. K., Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Menzies, J., P`ere, C., Pollard, K. R., Wouters, D., Christie, G., DePoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J. -R., Lee, C. -U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I. -G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., and Yonehara, P. C. M. Yock A.
Abstract: We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve, especially the perturbation part, allowed us to accurately measure the parallax effect and lens orbital motion. Combining our measurement of the lens parallax with the angular Einstein radius determined from finite-source effects, we estimate the physical parameters of the lens system. We find that the event was caused by a $2.73\pm 0.43\ M_{\rm J}$ planet orbiting a $0.44\pm 0.07\ M_{\odot}$ early M-type star. The distance to the lens is $4.97\pm 0.29$\ kpc and the projected separation between the host star and its planet at the time of the event is $3.45\pm 0.26$ AU. We find that the additional coverage provided by follow-up observations, especially during the planetary perturbation, leads to a more accurate determination of the physical parameters of the lens., Comment: 9 pages, 4 figures, accepted by ApJ
Published: 2013
Full Text: View/download PDF

35. Interpretation of a Short-Term Anomaly in the Gravitational Microlensing Event MOA-2012-BLG-486

Author: Hwang, K. -H., Choi, J. -Y., Bond, I. A., Sumi, T., Han, C., Gaudi, B. S., Gould, A., Bozza, V., Beaulieu, J. -P., Tsapras, Y., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Fukunaga, D., Harris, P., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., de Almeida, L. Andrade, DePoy, D. L., Dong, Subo, Jablonski, F., Jung, Y. K., Kavka, A., Lee, C. -U., Park, H., Pogge, R. W., Shin, I. -G., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Jørgensen, U. G., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Bramich, D. M., Dominik, M., Horne, K., Browne, P., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Street, R. A., Hwang, K. -H., Choi, J. -Y., Bond, I. A., Sumi, T., Han, C., Gaudi, B. S., Gould, A., Bozza, V., Beaulieu, J. -P., Tsapras, Y., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Fukunaga, D., Harris, P., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To., Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., de Almeida, L. Andrade, DePoy, D. L., Dong, Subo, Jablonski, F., Jung, Y. K., Kavka, A., Lee, C. -U., Park, H., Pogge, R. W., Shin, I. -G., Yee, J. C., Albrow, M. D., Bachelet, E., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Jørgensen, U. G., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Bramich, D. M., Dominik, M., Horne, K., Browne, P., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., and Street, R. A.
Abstract: A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals., Comment: 5 pages, 4 figures and ApJ submitted
Published: 2013
Full Text: View/download PDF

36. Gravitational Binary-lens Events with Prominent Effects of Lens Orbital Motion

Author: Park, H., Udalski, A., Han, C., Gould, A., Beaulieu, J. -P., Tsapras, Y., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Choi, J. -Y., Depoy, D. L., Dong, Subo, Gaudi, B. S., Hwang, K. -H., Jung, Y. K., Kavka, A., Lee, C. -U., Monard, L. A. G., Park, B. -G., Pogge, R. W., Porritt, I., Shin, I. -G., Yee, J. C., Albrow, M. D., Bennett, D. P., Caldwell, J. A. R., Cassan, A., Coutures, C., Dominis, D., Donatowicz, J., Fouqué, P., Greenhill, J., Huber, M., Jørgensen, U. G., Kane, S., Kubas, D., Marquette, J. -B., Menzies, J., Pitrou, C., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Allan, A., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Kains, N., Snodgrass, C., Steele, I. A., Street, R. A., Park, H., Udalski, A., Han, C., Gould, A., Beaulieu, J. -P., Tsapras, Y., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Choi, J. -Y., Depoy, D. L., Dong, Subo, Gaudi, B. S., Hwang, K. -H., Jung, Y. K., Kavka, A., Lee, C. -U., Monard, L. A. G., Park, B. -G., Pogge, R. W., Porritt, I., Shin, I. -G., Yee, J. C., Albrow, M. D., Bennett, D. P., Caldwell, J. A. R., Cassan, A., Coutures, C., Dominis, D., Donatowicz, J., Fouqué, P., Greenhill, J., Huber, M., Jørgensen, U. G., Kane, S., Kubas, D., Marquette, J. -B., Menzies, J., Pitrou, C., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Allan, A., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Kains, N., Snodgrass, C., Steele, I. A., and Street, R. A.
Abstract: Gravitational microlensing events produced by lenses composed of binary masses are important because they provide a major channel to determine physical parameters of lenses. In this work, we analyze the light curves of two binary-lens events OGLE-2006-BLG-277 and OGLE-2012-BLG-0031 for which the light curves exhibit strong deviations from standard models. From modeling considering various second-order effects, we find that the deviations are mostly explained by the effect of the lens orbital motion. We also find that lens parallax effects can mimic orbital effects to some extent. This implies that modeling light curves of binary-lens events not considering orbital effects can result in lens parallaxes that are substantially different from actual values and thus wrong determinations of physical lens parameters. This demonstrates the importance of routine consideration of orbital effects in interpreting light curves of binary-lens events. It is found that the lens of OGLE-2006-BLG-277 is a binary composed of a low-mass star and a brown dwarf companion., Comment: 6 pages and 4 figures
Published: 2013
Full Text: View/download PDF

37. A giant planet beyond the snow line in microlensing event OGLE-2011-BLG-0251

Author: Kains, N., Street, R. A., Choi, J.-Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P. J., Jørgensen, U. G., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dominik, M., Dreizler, S., Fang, X.-S., Grundahl, Frank, Gu, C.-H., Hardis, S., Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, Jens, Kerins, E., Liebig, C., Lund, Mikkel, Lundkvist, Mia, Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S.-J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y.-K., Koo, J.-R., Lee, C.-U., McCormick, J., McGregor, D., Muñoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Dominis Prester, D., Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J.-B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Zub, M., Kains, N., Street, R. A., Choi, J.-Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P. J., Jørgensen, U. G., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dominik, M., Dreizler, S., Fang, X.-S., Grundahl, Frank, Gu, C.-H., Hardis, S., Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, Jens, Kerins, E., Liebig, C., Lund, Mikkel, Lundkvist, Mia, Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S.-J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y.-K., Koo, J.-R., Lee, C.-U., McCormick, J., McGregor, D., Muñoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Dominis Prester, D., Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J.-B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., and Zub, M.
Published: 2013

38. A giant planet beyond the snow line in microlensing event OGLE-2011-BLG-0251

Author: Kains, N., Street, R. A., Choi, J.-Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P. J., Jørgensen, U. G., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dominik, M., Dreizler, S., Fang, X.-S., Grundahl, Frank, Gu, C.-H., Hardis, S., Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, Jens, Kerins, E., Liebig, C., Lund, Mikkel, Lundkvist, Mia, Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S.-J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y.-K., Koo, J.-R., Lee, C.-U., McCormick, J., McGregor, D., Muñoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Dominis Prester, D., Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J.-B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., Zub, M., Kains, N., Street, R. A., Choi, J.-Y., Han, C., Udalski, A., Almeida, L. A., Jablonski, F., Tristram, P. J., Jørgensen, U. G., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Wyrzykowski, Ł., Skowron, J., Alsubai, K. A., Bozza, V., Browne, P., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dominik, M., Dreizler, S., Fang, X.-S., Grundahl, Frank, Gu, C.-H., Hardis, S., Harpsøe, Kennet Bomann West, Hessman, F. V., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, Jens, Kerins, E., Liebig, C., Lund, Mikkel, Lundkvist, Mia, Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Sahu, K. C., Scarpetta, G., Skottfelt, J., Snodgrass, C., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Bajek, D., Bramich, D. M., Horne, K., Ipatov, S., Steele, I. A., Tsapras, Y., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Rattenbury, N., Saito, T., Sullivan, D. J., Sumi, T., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Wada, K., Yock, P. C. M., Allen, W., Batista, V., Chung, S.-J., Christie, G., DePoy, D. L., Drummond, J., Gaudi, B. S., Gould, A., Henderson, C., Jung, Y.-K., Koo, J.-R., Lee, C.-U., McCormick, J., McGregor, D., Muñoz, J. A., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Yee, J., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Dominis Prester, D., Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J.-B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Williams, A., Wouters, D., and Zub, M.
Published: 2013

39. Microlensing Binaries with Candidate Brown Dwarf Companions

Author: Shin, I.-G, Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J.-P, Tsapras, Y., Bozza, V., Szyman´ski, M. K., Kubiak, M., Soszyn´ski, I., Pietrzyn´ski, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To, Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L.-W, Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T.-G, Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J.-Y, Jung, Y.-K, Park, H., Lee, C.-U, Park, B.-G, Koo, J.-R, Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dreizler, S., Fang, X.-S, Grundahl, F., Gu, C.-H, Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, Allan, Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch, Dieters, S., Dominis Prester, D., Donatowicz, J., Fouque´, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J.-B, Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., Zub, M., Shin, I.-G, Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J.-P, Tsapras, Y., Bozza, V., Szyman´ski, M. K., Kubiak, M., Soszyn´ski, I., Pietrzyn´ski, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To, Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L.-W, Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T.-G, Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J.-Y, Jung, Y.-K, Park, H., Lee, C.-U, Park, B.-G, Koo, J.-R, Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Calchi Novati, S., Dodds, P., Dreizler, S., Fang, X.-S, Grundahl, F., Gu, C.-H, Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, Allan, Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch, Dieters, S., Dominis Prester, D., Donatowicz, J., Fouque´, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J.-B, Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., and Zub, M.
Abstract: Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation histories. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing events discovered during the 2004-2011 observation seasons. Based on the low mass ratio criterion of q <0.2, we found seven candidate events: OGLE-2004-BLG-035, OGLE-2004-BLG-039, OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334, MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the lens based on the simultaneous measurement of the Einstein radius and the lens parallax. The measured masses of the brown dwarf companions are 0.02 ± 0.01 M⊙ and 0.019 ± 0.002 M⊙ for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low-mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events with well-covered light curves increases with new-generation searches.
Published: 2012

40. MOA-2010-BLG-073L: An M-Dwarf with a Substellar Companion at the Planet/Brown Dwarf Boundary

Author: Street, R. A., Choi, J. -Y., Tsapras, Y., Han, C., Furusawa, K., Hundertmark, M., Gould, A., Sumi, T., Bond, I. A., Wouters, D., Zellem, R., Udalski, A., Snodgrass, C., Horne, K., Dominik, M., Browne, P., Kains, N., Bramich, D. M., Bajek, D., Steele, I. A., Ipatov, S., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Harris, P., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagayama, T., Nishimaya, S., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Ulaczyk, K., Wyrzykowski, L., Yee, J., Dong, S., Shin, I. -G., Lee, C. -U., Skowron, J., De Almeida, L. Andrade, DePoy, D. L., Gaudi, B. S., Hung, L. -W., Jablonski, F., Kaspi, S., Klein, N., Hwang, K. -H., Koo, J. -R., Maoz, D., Munoz, J. A., Pogge, R. W., Polishhook, D., Shporer, A., McCormick, J., Christie, G., Natusch, T., Allen, B., Drummond, J., Moorhouse, D., Thornley, G., Knowler, M., Bos, M., Bolt, G., Beaulieu, J. -P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Bachelet, E., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Alsubai, K. A., Bozza, V., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Finet, F., Gerner, T., Hardis, S., Harpsoe, K., Hessman, F., Hinse, T. C., Jorgensen, U. G., Kerins, E., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Schafer, S., Schonebeck, F., Southworth, J., Surdej, J., Street, R. A., Choi, J. -Y., Tsapras, Y., Han, C., Furusawa, K., Hundertmark, M., Gould, A., Sumi, T., Bond, I. A., Wouters, D., Zellem, R., Udalski, A., Snodgrass, C., Horne, K., Dominik, M., Browne, P., Kains, N., Bramich, D. M., Bajek, D., Steele, I. A., Ipatov, S., Abe, F., Bennett, D. P., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Harris, P., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagayama, T., Nishimaya, S., Ohnishi, K., Rattenbury, N., Saito, To., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Ulaczyk, K., Wyrzykowski, L., Yee, J., Dong, S., Shin, I. -G., Lee, C. -U., Skowron, J., De Almeida, L. Andrade, DePoy, D. L., Gaudi, B. S., Hung, L. -W., Jablonski, F., Kaspi, S., Klein, N., Hwang, K. -H., Koo, J. -R., Maoz, D., Munoz, J. A., Pogge, R. W., Polishhook, D., Shporer, A., McCormick, J., Christie, G., Natusch, T., Allen, B., Drummond, J., Moorhouse, D., Thornley, G., Knowler, M., Bos, M., Bolt, G., Beaulieu, J. -P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Bachelet, E., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Alsubai, K. A., Bozza, V., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Finet, F., Gerner, T., Hardis, S., Harpsoe, K., Hessman, F., Hinse, T. C., Jorgensen, U. G., Kerins, E., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Schafer, S., Schonebeck, F., Southworth, J., and Surdej, J.
Abstract: We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010-03-18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source lightcurve, we demonstrate that it is an irregular variable over time scales >200d. Its dereddened color, $(V-I)_{S,0}$, is 1.221$\pm$0.051mag and from our lens model we derive a source radius of 14.7$\pm$1.3 $R_{\odot}$, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q=0.0654$\pm$0.0006. The Einstein crossing time of the event, $T_{\rm{E}}=44.3$\pm$0.1d, was sufficiently long that the lightcurve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, $D_L$=2.8$\pm$0.4kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with $M_{L,p}$=0.16$\pm0.03M_{\odot}$ while the companion has $M_{L,s}$=11.0$\pm2.0M_{\rm{J}}$ putting it in the boundary zone between planets and brown dwarfs., Comment: 24 pages, 8 figures, best viewed in colour, accepted by ApJ
Published: 2012
Full Text: View/download PDF

41. Spectroscopic Pulsational Frequency Identification and Mode Determination of {\gamma} Doradus Star HD 12901

Author: Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., De Cat, P., Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., and De Cat, P.
Abstract: Using multi-site spectroscopic data collected from three sites, the frequencies and pulsational modes of the {\gamma} Doradus star HD 12901 were identified. A total of six frequencies in the range 1-2 c/d were observed, their identifications supported by multiple line-profile measurement techniques and previously-published photometry. Five frequencies were of sufficient signal-to-noise for mode identification and all five displayed similar three-bump standard deviation profiles which were fitted well with (l,m)=(1,1) modes. These fits had reduced chi-squared values of less than 18. We propose that this star is an excellent candidate to test models of non-radially pulsating {\gamma} Doradus stars as a result of the presence of multiple (1,1) modes., Comment: Accepted for publication in MNRAS, 13 September 2012
Published: 2012
Full Text: View/download PDF

42. Microlensig Binaries with Candidate Brown Dwarf Companions

Author: Shin, I. -G., Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J. -P., Tsapras, Y., Bozza, V., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To., Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L. -W., Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T. -G., Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J. -Y., Jung, Y. -K., Park, H., Lee, C. -U., Park, B. -G., Koo, J. -R., Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, A., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., Zub, M., Shin, I. -G., Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J. -P., Tsapras, Y., Bozza, V., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To., Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L. -W., Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T. -G., Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J. -Y., Jung, Y. -K., Park, H., Lee, C. -U., Park, B. -G., Koo, J. -R., Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, A., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., and Zub, M.
Abstract: Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation history. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing events discovered during 2004 - 2011 observation seasons. Based on the low mass ratio criterion of q < 0.2, we found 7 candidate events, including OGLE-2004-BLG-035, OGLE-2004-BLG-039, OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334, MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the lens based on the simultaneous measurement of the Einstein radius and the lens parallax. The measured mass of the brown dwarf companions are (0.02 +/- 0.01) M_Sun and (0.019 +/- 0.002) M_Sun for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events with well covered light curves increases with new generation searches., Comment: 10 pages, 9 figures, 4 tables
Published: 2012
Full Text: View/download PDF

43. A possible binary system of a stellar remnant in the high magnification gravitational microlensing event OGLE-2007-BLG-514

Author: Miyake, N., Udalski, A., Sumi, T., Bennett, D. P., Dong, S., Street, R. A., Greenhill, J., Bond, I. A., Gould, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Abe, F., Fukui, A., Furusawa, K., Holderness, S., Itow, Y., Korpela, A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagayama, T., Ohnishi, K., Rattenbury, N., Saito, To., Sako, T., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Allen, W., Christie, G. W., DePoy, D. L., Gaudi, B. S., Han, C., Lee, C. -U., McCormick, J., Monard, B., Natusch, T., Park, B. -G., Pogge, R. W., Allan, A., Bode, M., Bramich, D. M., Clay, N., Dominik, M., Horne, K. D., Kains, N., Mottram, C., Snodgrass, C., Steele, I., Tsapras, Y., Albrow, M. D., Batista, V., Beaulieu, J. P., Brillant, S., Burgdorf, M., Caldwell, J. A. R., Cassan, A., Cole, A., Cook, K. H., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Jorgensen, U. G., Kane, S., Kubas, D., Marquette, J. B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Miyake, N., Udalski, A., Sumi, T., Bennett, D. P., Dong, S., Street, R. A., Greenhill, J., Bond, I. A., Gould, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Abe, F., Fukui, A., Furusawa, K., Holderness, S., Itow, Y., Korpela, A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagayama, T., Ohnishi, K., Rattenbury, N., Saito, To., Sako, T., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Allen, W., Christie, G. W., DePoy, D. L., Gaudi, B. S., Han, C., Lee, C. -U., McCormick, J., Monard, B., Natusch, T., Park, B. -G., Pogge, R. W., Allan, A., Bode, M., Bramich, D. M., Clay, N., Dominik, M., Horne, K. D., Kains, N., Mottram, C., Snodgrass, C., Steele, I., Tsapras, Y., Albrow, M. D., Batista, V., Beaulieu, J. P., Brillant, S., Burgdorf, M., Caldwell, J. A. R., Cassan, A., Cole, A., Cook, K. H., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Jorgensen, U. G., Kane, S., Kubas, D., Marquette, J. B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We report the extremely high magnification (A > 1000) binary microlensing event OGLE-2007-BLG-514. We obtained good coverage around the double peak structure in the light curve via follow-up observations from different observatories. The binary lens model that includes the effects of parallax (known orbital motion of the Earth) and orbital motion of the lens yields a binary lens mass ratio of q = 0.321 +/- 0.007 and a projected separation of s = 0.072 +/- 0.001$ in units of the Einstein radius. The parallax parameters allow us to determine the lens distance D_L = 3.11 +/- 0.39 kpc and total mass M_L=1.40 +/- 0.18 M_sun; this leads to the primary and secondary components having masses of M_1 = 1.06 +/- 0.13 M_sun and M_2 = 0.34 +/- 0.04 M_sun, respectively. The parallax model indicates that the binary lens system is likely constructed by the main sequence stars. On the other hand, we used a Bayesian analysis to estimate probability distributions by the model that includes the effects of xallarap (possible orbital motion of the source around a companion) and parallax (q = 0.270 +/- 0.005, s = 0.083 +/- 0.001). The primary component of the binary lens is relatively massive with M_1 = 0.9_{-0.3}^{+4.6} M_sun and it is at a distance of D_L = 2.6_{-0.9}^{+3.8} kpc. Given the secure mass ratio measurement, the companion mass is therefore M_2 = 0.2_{-0.1}^{+1.2} M_sun. The xallarap model implies that the primary lens is likely a stellar remnant, such as a white dwarf, a neutron star or a black hole., Comment: 31 pages, 6 figures, 7 tables, accepted in ApJ
Published: 2012
Full Text: View/download PDF

44. Spectroscopic Pulsational Frequency Identification and Mode Determination of Gamma Doradus Star HD135825

Author: Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., De Cat, P., Kilmartin, P. M., Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., De Cat, P., and Kilmartin, P. M.
Abstract: We present the mode identification of frequencies found in spectroscopic observations of the Gamma Doradus star HD135825. Four frequencies were successfully identified: 1.3150 +/- 0.0003 1/d; 0.2902 +/- 0.0004 1/d; 1.4045 +/- 0.0005 1/d; and 1.8829 +/- 0.0005 1/d. These correspond to (l, m) modes of (1,1), (2,-2), (4,0) and (1,1) respectively. Additional frequencies were found but they were below the signal-to-noise limit of the Fourier spectrum and not suitable for mode identification. The rotational axis inclination and vsini of the star were determined to be 87 degrees (nearly edge-on) and 39.7 km/s (moderate for Gamma Doradus stars) respectively. A simultaneous fit of these four modes to the line profile variations in the data gives a reduced chi square of 12.7. We confirm, based on the frequencies found, that HD135825 is a bona fide Gamma Doradus star., Comment: Accepted to MNRAS 2012 March 2
Published: 2012
Full Text: View/download PDF

45. OGLE-2008-BLG-510: first automated real-time detection of a weak microlensing anomaly - brown dwarf or stellar binary?

Author: Bozza, V., Dominik, M., Rattenbury, N. J., Joergensen, U. G., Tsapras, Y., Bramich, D. M., Udalski, A., Bond, I. A., Liebig, C., Cassan, A., Fouque, P., Fukui, A., Hundertmark, M., Shin, I. -G., Lee, S. H., Choi, J. -Y., Park, S. -Y., Gould, A., Allan, A., Mao, S., Wyrzykowski, L., Street, R. A., Buckley, D., Nagayama, T., Mathiasen, M., Hinse, T. C., Novati, S. Calchi, Harpsoee, K., Mancini, L., Scarpetta, G., Anguita, T., Burgdorf, M. J., Horne, K., Hornstrup, A., Kains, N., Kerins, E., Kjaergaard, P., Masi, G., Rahvar, S., Ricci, D., Snodgrass, C., Southworth, J., Steele, I. A., Surdej, J., Thoene, C. C., Wambsganss, J., Zub, M., Albrow, M. D., Batista, V., Beaulieu, J. -P., Bennett, D. P., Caldwell, J. A. R., Cole, A, Cook, K. H., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Williams, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Ulaczyk, K., DePoy, D. L., Dong, S., Han, C., Janczak, J., Lee, C. -U., Pogge, R. W., Abe, F., Furusawa, K., Hearnshaw, J. B., Itow, Y., Kilmartin, P. M., Korpela, A. V., Lin, W., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Perrott, Y. C., Saito, To., Skuljan, L., Sullivan, D. J., Sumi, T., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Gulbis, A., Hashimoto, Y., Kniazev, A., Vaisanen, P., Bozza, V., Dominik, M., Rattenbury, N. J., Joergensen, U. G., Tsapras, Y., Bramich, D. M., Udalski, A., Bond, I. A., Liebig, C., Cassan, A., Fouque, P., Fukui, A., Hundertmark, M., Shin, I. -G., Lee, S. H., Choi, J. -Y., Park, S. -Y., Gould, A., Allan, A., Mao, S., Wyrzykowski, L., Street, R. A., Buckley, D., Nagayama, T., Mathiasen, M., Hinse, T. C., Novati, S. Calchi, Harpsoee, K., Mancini, L., Scarpetta, G., Anguita, T., Burgdorf, M. J., Horne, K., Hornstrup, A., Kains, N., Kerins, E., Kjaergaard, P., Masi, G., Rahvar, S., Ricci, D., Snodgrass, C., Southworth, J., Steele, I. A., Surdej, J., Thoene, C. C., Wambsganss, J., Zub, M., Albrow, M. D., Batista, V., Beaulieu, J. -P., Bennett, D. P., Caldwell, J. A. R., Cole, A, Cook, K. H., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Williams, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Poleski, R., Ulaczyk, K., DePoy, D. L., Dong, S., Han, C., Janczak, J., Lee, C. -U., Pogge, R. W., Abe, F., Furusawa, K., Hearnshaw, J. B., Itow, Y., Kilmartin, P. M., Korpela, A. V., Lin, W., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohnishi, K., Perrott, Y. C., Saito, To., Skuljan, L., Sullivan, D. J., Sumi, T., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Gulbis, A., Hashimoto, Y., Kniazev, A., and Vaisanen, P.
Abstract: The microlensing event OGLE-2008-BLG-510 is characterised by an evident asymmetric shape of the peak, promptly detected by the ARTEMiS system in real time. The skewness of the light curve appears to be compatible both with binary-lens and binary-source models, including the possibility that the lens system consists of an M dwarf orbited by a brown dwarf. The detection of this microlensing anomaly and our analysis demonstrates that: 1) automated real-time detection of weak microlensing anomalies with immediate feedback is feasible, efficient, and sensitive, 2) rather common weak features intrinsically come with ambiguities that are not easily resolved from photometric light curves, 3) a modelling approach that finds all features of parameter space rather than just the `favourite model' is required, and 4) the data quality is most crucial, where systematics can be confused with real features, in particular small higher-order effects such as orbital motion signatures. It moreover becomes apparent that events with weak signatures are a silver mine for statistical studies, although not easy to exploit. Clues about the apparent paucity of both brown-dwarf companions and binary-source microlensing events might hide here., Comment: 17 pages with 8 figures, MNRAS submitted
Published: 2012
Full Text: View/download PDF

46. One or more bound planets per Milky Way star from microlensing observations

Author: Cassan, A., Kubas, D., Beaulieu, J. -P., Dominik, M., Horne, K., Greenhill, J., Wambsganss, J., Menzies, J., Williams, A., Jorgensen, U. G., Udalski, A., Bennett, D. P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, Ch., Cook, K. H., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hill, K., Kains, N., Kane, S., Marquette, J. -B., Martin, R., Pollard, K. R., Sahu, K. C., Vinter, C., Warren, D., Watson, B., Zub, M., Sumi, T., Szymanski, M. K., Kubiak, M., Poleski, R., Soszynski, I., Ulaczyk, K., Pietrzynski, G., Wyrzykowski, L., Cassan, A., Kubas, D., Beaulieu, J. -P., Dominik, M., Horne, K., Greenhill, J., Wambsganss, J., Menzies, J., Williams, A., Jorgensen, U. G., Udalski, A., Bennett, D. P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, Ch., Cook, K. H., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hill, K., Kains, N., Kane, S., Marquette, J. -B., Martin, R., Pollard, K. R., Sahu, K. C., Vinter, C., Warren, D., Watson, B., Zub, M., Sumi, T., Szymanski, M. K., Kubiak, M., Poleski, R., Soszynski, I., Ulaczyk, K., Pietrzynski, G., and Wyrzykowski, L.
Abstract: Most known extrasolar planets (exoplanets) have been discovered using the radial velocity$^{\bf 1,2}$ or transit$^{\bf 3}$ methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17--30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing$^{\bf 6\rm{\bf -}\bf 9}$, on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing$^{\bf 10}$. These planets are at least as numerous as the stars in the Milky Way$^{\bf 10}$. Here we report a statistical analysis of microlensing data (gathered in 2002--07) that reveals the fraction of bound planets 0.5--10 AU (Sun--Earth distance) from their stars. We find that 17$_{\bf -9}^{\bf +6}$% of stars host Jupiter-mass planets (0.3--10 $\MJ$, where $\MJ {\bf = 318}$ $\Mearth$ and $\Mearth$ is Earth's mass). Cool Neptunes (10--30 $\Mearth$) and super-Earths (5--10 $\Mearth$) are even more common: their respective abundances per star are 52$_{\bf -29}^{\bf +22}$% and 62$_{\bf -37}^{\bf +35}$%. We conclude that stars are orbited by planets as a rule, rather than the exception., Comment: Letter, 2 figures
Published: 2012
Full Text: View/download PDF

47. One or more bound planets per Milky Way star from microlensing observations

Author: Cassan, A., Kubas, D., Beaulieu, J. -P., Dominik, M., Horne, K., Greenhill, J., Wambsganss, J., Menzies, J., Williams, A., Jorgensen, U. G., Udalski, A., Bennett, D. P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, Ch., Cook, K. H., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hill, K., Kains, N., Kane, S., Marquette, J. -B., Martin, R., Pollard, K. R., Sahu, K. C., Vinter, C., Warren, D., Watson, B., Zub, M., Sumi, T., Szymanski, M. K., Kubiak, M., Poleski, R., Soszynski, I., Ulaczyk, K., Pietrzynski, G., Wyrzykowski, L., Cassan, A., Kubas, D., Beaulieu, J. -P., Dominik, M., Horne, K., Greenhill, J., Wambsganss, J., Menzies, J., Williams, A., Jorgensen, U. G., Udalski, A., Bennett, D. P., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Cole, A., Coutures, Ch., Cook, K. H., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Hill, K., Kains, N., Kane, S., Marquette, J. -B., Martin, R., Pollard, K. R., Sahu, K. C., Vinter, C., Warren, D., Watson, B., Zub, M., Sumi, T., Szymanski, M. K., Kubiak, M., Poleski, R., Soszynski, I., Ulaczyk, K., Pietrzynski, G., and Wyrzykowski, L.
Abstract: Most known extrasolar planets (exoplanets) have been discovered using the radial velocity$^{\bf 1,2}$ or transit$^{\bf 3}$ methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17--30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing$^{\bf 6\rm{\bf -}\bf 9}$, on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing$^{\bf 10}$. These planets are at least as numerous as the stars in the Milky Way$^{\bf 10}$. Here we report a statistical analysis of microlensing data (gathered in 2002--07) that reveals the fraction of bound planets 0.5--10 AU (Sun--Earth distance) from their stars. We find that 17$_{\bf -9}^{\bf +6}$% of stars host Jupiter-mass planets (0.3--10 $\MJ$, where $\MJ {\bf = 318}$ $\Mearth$ and $\Mearth$ is Earth's mass). Cool Neptunes (10--30 $\Mearth$) and super-Earths (5--10 $\Mearth$) are even more common: their respective abundances per star are 52$_{\bf -29}^{\bf +22}$% and 62$_{\bf -37}^{\bf +35}$%. We conclude that stars are orbited by planets as a rule, rather than the exception., Comment: Letter, 2 figures
Published: 2012
Full Text: View/download PDF

48. Spectroscopic Pulsational Frequency Identification and Mode Determination of {\gamma} Doradus Star HD 12901

Author: Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., De Cat, P., Brunsden, E., Pollard, K. R., Cottrell, P. L., Wright, D. J., and De Cat, P.
Abstract: Using multi-site spectroscopic data collected from three sites, the frequencies and pulsational modes of the {\gamma} Doradus star HD 12901 were identified. A total of six frequencies in the range 1-2 c/d were observed, their identifications supported by multiple line-profile measurement techniques and previously-published photometry. Five frequencies were of sufficient signal-to-noise for mode identification and all five displayed similar three-bump standard deviation profiles which were fitted well with (l,m)=(1,1) modes. These fits had reduced chi-squared values of less than 18. We propose that this star is an excellent candidate to test models of non-radially pulsating {\gamma} Doradus stars as a result of the presence of multiple (1,1) modes., Comment: Accepted for publication in MNRAS, 13 September 2012
Published: 2012
Full Text: View/download PDF

49. Microlensig Binaries with Candidate Brown Dwarf Companions

Author: Shin, I. -G., Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J. -P., Tsapras, Y., Bozza, V., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To., Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L. -W., Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T. -G., Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J. -Y., Jung, Y. -K., Park, H., Lee, C. -U., Park, B. -G., Koo, J. -R., Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, A., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., Zub, M., Shin, I. -G., Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J. -P., Tsapras, Y., Bozza, V., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To., Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L. -W., Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T. -G., Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J. -Y., Jung, Y. -K., Park, H., Lee, C. -U., Park, B. -G., Koo, J. -R., Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X. -S., Grundahl, F., Gu, C. -H., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, A., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J. -B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., and Zub, M.
Abstract: Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation history. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing events discovered during 2004 - 2011 observation seasons. Based on the low mass ratio criterion of q < 0.2, we found 7 candidate events, including OGLE-2004-BLG-035, OGLE-2004-BLG-039, OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334, MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the lens based on the simultaneous measurement of the Einstein radius and the lens parallax. The measured mass of the brown dwarf companions are (0.02 +/- 0.01) M_Sun and (0.019 +/- 0.002) M_Sun for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events with well covered light curves increases with new generation searches., Comment: 10 pages, 9 figures, 4 tables
Published: 2012
Full Text: View/download PDF

50. A possible binary system of a stellar remnant in the high magnification gravitational microlensing event OGLE-2007-BLG-514

Author: Miyake, N., Udalski, A., Sumi, T., Bennett, D. P., Dong, S., Street, R. A., Greenhill, J., Bond, I. A., Gould, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Abe, F., Fukui, A., Furusawa, K., Holderness, S., Itow, Y., Korpela, A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagayama, T., Ohnishi, K., Rattenbury, N., Saito, To., Sako, T., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Allen, W., Christie, G. W., DePoy, D. L., Gaudi, B. S., Han, C., Lee, C. -U., McCormick, J., Monard, B., Natusch, T., Park, B. -G., Pogge, R. W., Allan, A., Bode, M., Bramich, D. M., Clay, N., Dominik, M., Horne, K. D., Kains, N., Mottram, C., Snodgrass, C., Steele, I., Tsapras, Y., Albrow, M. D., Batista, V., Beaulieu, J. P., Brillant, S., Burgdorf, M., Caldwell, J. A. R., Cassan, A., Cole, A., Cook, K. H., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Jorgensen, U. G., Kane, S., Kubas, D., Marquette, J. B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Miyake, N., Udalski, A., Sumi, T., Bennett, D. P., Dong, S., Street, R. A., Greenhill, J., Bond, I. A., Gould, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Soszynski, I., Ulaczyk, K., Wyrzykowski, L., Abe, F., Fukui, A., Furusawa, K., Holderness, S., Itow, Y., Korpela, A., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Nagayama, T., Ohnishi, K., Rattenbury, N., Saito, To., Sako, T., Sullivan, D. J., Sweatman, W. L., Tristram, P. J., Yock, P. C. M., Allen, W., Christie, G. W., DePoy, D. L., Gaudi, B. S., Han, C., Lee, C. -U., McCormick, J., Monard, B., Natusch, T., Park, B. -G., Pogge, R. W., Allan, A., Bode, M., Bramich, D. M., Clay, N., Dominik, M., Horne, K. D., Kains, N., Mottram, C., Snodgrass, C., Steele, I., Tsapras, Y., Albrow, M. D., Batista, V., Beaulieu, J. P., Brillant, S., Burgdorf, M., Caldwell, J. A. R., Cassan, A., Cole, A., Cook, K. H., Coutures, Ch., Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouque, P., Jorgensen, U. G., Kane, S., Kubas, D., Marquette, J. B., Martin, R., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., and Zub, M.
Abstract: We report the extremely high magnification (A > 1000) binary microlensing event OGLE-2007-BLG-514. We obtained good coverage around the double peak structure in the light curve via follow-up observations from different observatories. The binary lens model that includes the effects of parallax (known orbital motion of the Earth) and orbital motion of the lens yields a binary lens mass ratio of q = 0.321 +/- 0.007 and a projected separation of s = 0.072 +/- 0.001$ in units of the Einstein radius. The parallax parameters allow us to determine the lens distance D_L = 3.11 +/- 0.39 kpc and total mass M_L=1.40 +/- 0.18 M_sun; this leads to the primary and secondary components having masses of M_1 = 1.06 +/- 0.13 M_sun and M_2 = 0.34 +/- 0.04 M_sun, respectively. The parallax model indicates that the binary lens system is likely constructed by the main sequence stars. On the other hand, we used a Bayesian analysis to estimate probability distributions by the model that includes the effects of xallarap (possible orbital motion of the source around a companion) and parallax (q = 0.270 +/- 0.005, s = 0.083 +/- 0.001). The primary component of the binary lens is relatively massive with M_1 = 0.9_{-0.3}^{+4.6} M_sun and it is at a distance of D_L = 2.6_{-0.9}^{+3.8} kpc. Given the secure mass ratio measurement, the companion mass is therefore M_2 = 0.2_{-0.1}^{+1.2} M_sun. The xallarap model implies that the primary lens is likely a stellar remnant, such as a white dwarf, a neutron star or a black hole., Comment: 31 pages, 6 figures, 7 tables, accepted in ApJ
Published: 2012
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Publication Year Range

Publication Type

Database

Publisher

129 results on '"Pollard, K. R."'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources