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330 results on '"Stecklum B"'

302. Polarimetric studies of gamma-ray burst afterglows.

Author

Klose, S., Stecklum, B., and Fischer, O.

Subjects
*GAMMA ray bursts, *AFTERGLOW (Physics)
Abstract

We report on a target of opportunity program to study GRB afterglows based on observations with the Calar Alto 3.5-m telescope equipped with the near-infrared camera Omega Cass. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2000

303. Spectroscopic distances of 28 nearby star candidates

Author

Jahrei?, H., Meusinger, H., Scholz, R.-D., and Stecklum, B.

Abstract

Aims. Twenty eight hitherto neglected candidates for the Catalogue of Nearby Stars (CNS) were investigated to verify their classification and to improve their distance estimates. All targets had at least a preliminary status of being nearby dwarf stars based on their large proper motions and relatively faint magnitudes. Better photometric and/or spectroscopic distances were required for selecting stars for further trigonometric parallax measurements.Methods. Low-resolution spectra were obtained with NASPEC at the Tautenburg 2?m telescope and with CAFOS at the Calar Alto 2.2?m telescope. The spectral types of M-type stars were determined by direct comparison of the target's spectra with those of comparison stars of known spectral types observed with the same instrument. The classification of earlier types was performed based on comparison with published spectral libraries.Results. For most of the target stars reliable spectral types could be determined and in combination with 2MASS?photometry new improved distance estimates became available. The majority were classified as M?dwarfs including 11?stars within 25?pc. The fainter component of LDS?1365, previously thought to form a nearby common proper motion pair, is according to our results an unrelated high-velocity background star. For several other nearby common proper motion pairs our distance estimates of the fainter components are in good agreement with Hipparcos distances of the brighter components. The three stars in our sample that were previously thought to be white dwarfs (GJ?2091, GJ?2094, GJ?2098) turned out to be more distant high-velocity F- to K-type (sub)dwarfs. For the star with the largest tangential velocity (GJ?2091; vtan>500?km?s-1) we have additional evidence for its probable Galactic halo membership from a measured large radial velocity of 266?? 25?km?s-1and from its UBV?photometry indicating a low metallicity.

Published
2008

304. Measuring the ionisation fraction in a jet from a massive protostar.

Author

Purser, S. J. D., Garcia-Lopez, R., Ray, T. P., Fedriani, R., Caratti o Garatti, A., Coffey, D., Sanna, A., Tan, J. C., Stecklum, B., and Hoare, M.

Subjects
PROTOSTARS, IONIZATION (Atomic physics), JETS (Nuclear physics), ANGULAR momentum (Nuclear physics), MASS spectrometry
Abstract

It is important to determine if massive stars form via disc accretion, like their low-mass counterparts. Theory and observation indicate that protostellar jets are a natural consequence of accretion discs and are likely to be crucial for removing angular momentum during the collapse. However, massive protostars are typically rarer, more distant and more dust enshrouded, making observational studies of their jets more challenging. A fundamental question is whether the degree of ionisation in jets is similar across the mass spectrum. Here we determine an ionisation fraction of ~5–12% in the jet from the massive protostar G35.20-0.74N, based on spatially coincident infrared and radio emission. This is similar to the values found in jets from lower-mass young stars, implying a unified mechanism of shock ionisation applies in jets across most of the protostellar mass spectrum, up to at least ~10 solar masses. The ionisation fraction of protostellar jets is key to establish their true energetics. Here, the authors determine it in a jet from a high-mass young stellar object, using multi-wavelengths observations, confirming that the ionising mechanism giving rise to the radio emission originates from shocks. [ABSTRACT FROM AUTHOR]

Published
2019
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305. GRB 011121: Jet, wind and supernova -- all in one

Author

Greiner, J., Klose, S., Salvato, M., Zeh, A., Schwarz, R., Hartmann, D. H., Masetti, N., Stecklum, B., Lamer, G., Lodieu, N., Scholz, R. D., Sterken, C., Gorosabel, J., Burud, I., Rhoads, J., Mitrofanov, I., Litvak, M., Sanin, A., Grinkov, V., Andersen, M. I., Castro Cerón, J. M., Castro-Tirado, A. J., Fruchter, A., Fynbo, J. U., Hjorth, J., Kaper, L., Kouveliotou, C., Eliana Palazzi, Pian, E., Rol, E., Salamanca, I., Tanvir, N. R., Vreeswijk, P. M., Wijers, R. A. M. J., and Den Heuvel, E.

306. The polarization evolution of the optical afterglow of GRB 030329

Author

Greiner, J., Klose, S., Reinsch, K., Schmid, Hm, Sari, R., Hartmann, Dh, Kouveliotou, C., Rau, A., Palazzi, E., Straubmeier, C., Stecklum, B., Zharikov, S., Tovmassian, G., Barnbantner, O., Ries, C., Jehin, E., Henden, A., Kaas, Ss, Grav, T., Hjorth, J., Pedersen, H., Wijers, Ramj, Kaufer, A., Park, Hs, Williams, G., Olaf Reimer, Fenimore, Ee, Galassi, M., and High Energy Astrophys. & Astropart. Phys (API, FNWI)

Abstract

Not Available

309. Recent updates on the Maser Monitoring Organisation

Author

Burns, R. A., Kobak, A., Caratti O Garatti, A., Tolmachev, A., Volvach, A., Alakoz, A., Wootten, A., Bisyarina, A., Dzodzomenyo, A., Sobolev, A., Bartkiewicz, A., Aberfelds, A., Stecklum, B., Kramer, B., Macdonald, C., Cyganowski, C., Colomer, F., Miro, C. G., Brogan, C., Li, D., Smits, D., Engels, D., Ladeyschikov, D., Johnstone, D., Elena Popova, Proven-Adzri, E., Den Heever, F., Orosz, G., Surcis, G., Wu, G., Macleod, G., Linz, H., Imai, H., Langevelde, H., Valtts, I., Shmeld, I., Chibueze, J. O., Brand, J., Kumar, J., Green, J., Vorster, J., Eislöffel, J., Kim, J., Sugiyama, K., Menten, K., Immer, K., Sunada, K., Kim, K. -T, Volvach, L., Moscadelli, L., Jordan, L., Uscanga, L., Gray, M., Szymczak, M., Olech, M., Hoare, M., Durjasz, M., Uchiyama, M., Shakhvorostova, N., Bayandina, O., Wolak, P., Gulyaev, S., Khaibrakhmanov, S., Breen, S., Goedhart, S., Casu, S., Ellingsen, S., Kurtz, S., Weston, S., Yoshihiro, T., Natusch, T., Hunter, T., Hirota, T., Baan, W., Vlemmings, W., Chen, X., Gong, Y., Yonekura, Y., Szabó, Z. M., Abraham, Z., ITA, USA, GBR, FRA, DEU, ESP, AUS, CAN, KOR, JPN, CHN, and RUS

Abstract

The Maser Monitoring Organisation (M2O) is a research community of telescope operators, astronomy researchers and maser theoreticians pursuing a joint goal of reaching a deeper understanding of maser emission and exploring its variety of uses as tracers of astrophysical events. These proceedings detail the origin, motivations and current status of the M2O, as was introduced at the 2021 EVN symposium.

312. Searching for H2 emission from protoplanetary disks using near- and mid-infrared high-resolution spectroscopy

Author

Carmona, A., van den Ancker, M. E., Henning, Th, Pavlyuchenkov, Ya, Dullemond, C. P., Goto, M., Fedele, D., Stecklum, B., F-.Thi, W., Bouwman, J., Waters, L. B. F. M., Carmona, A., van den Ancker, M. E., Henning, Th, Pavlyuchenkov, Ya, Dullemond, C. P., Goto, M., Fedele, D., Stecklum, B., F-.Thi, W., Bouwman, J., and Waters, L. B. F. M.

Abstract

The mass and dynamics of protoplanetary disks are dominated by molecular hydrogen (H2). However, observationally very little is known about the H2. In this paper, we discuss two projects aimed to constrain the properties of H2 in the disk's planet forming region (R<50AU). First, we present a sensitive survey for pure-rotational H2 emission at 12.278 and 17.035 μm in a sample of nearby Herbig Ae/Be and T Tauri stars using VISIR, ESO's VLT high-resolution mid-infrared spectrograph. Second, we report on a search for H2 ro-vibrational emission at 2.1228, 2.2233 and 2.2477 μm in the classical T Tauri star LkHα 264 and the debris disk 49 Cet employing CRIRES, ESO's VLT high-resolution near-infrared spectrograph. VISIR project: none of the sources show H2 mid-IR emission. The observed disks contain less than a few tenths of MJupiter of optically thin H2 at 150 K, and less than a few MEarth at T>300 K. % and higher T. Our non-detections are consistent with the low flux levels expected from the small amount of H2 gas in the surface layer of a Chiang and Goldreich (1997) Herbig Ae two-layer disk model. In our sources the H2 and dust in the surface layer have not significantly departed from thermal coupling (Tgas/Tdust<2) and the gas-to-dust ratio in the surface layer is very likely <1000. CRIRES project: The H2 lines at 2.1218 μm and 2.2233 μm are detected in LkHα 264. An upper limit on the 2.2477 μm H2 line flux in LkHα 264 is derived. 49 Cet does not exhibit H2 emission in any of observed lines. There are a few MMoon of optically thin hot H2 in the inner disk (0.1 AU) of LkHα 264, and less than a tenth of a MMoon of hot H2 in the inner disk of 49 Cet. The shape of the 1-0 S(0) line indicates that LkHα disk is close to face-on (i<35o). The measured 1-0 S(0)/1-0 S(1) and 2-1 S(1)/1-0 S(1) line ratios in LkHα 264 indicate that the H2 is thermally excited at T<1500 K. The lack of H2 emission in the NIR spectra of 49 Cet and the absence of Hα emission suggest that the gas in the

313. The afterglows of Swift-era gamma-ray bursts. I. Comparing pre-Swift and Swift-era long/soft (type II) GRB optical afterglows

Author

Kann D., Klose S., Zhang B., Malesani D., Nakar E., Pozanenko A., Wilson A., Butler N., Jakobsson P., Schulze S., Andreev M., Antonelli L., Bikmaev I., Biryukov V., Böttcher M., Burenin R., Cerón J., Castro-Tirado A., Chincarini G., Cobb B., Covino S., D'Avanzo P., D'Elia V., Valle M., De Ugarte Postigo A., Efimov Y., Ferrero P., Fugazza D., Fynbo J., Gålfalk M., Grundahl F., Gorosabel J., Gupta S., Guziy S., Hafizov B., Hjorth J., Holhjem K., Ibrahimov M., Im M., Israel G., Jelainek M., Jensen B., Karimov R., Khamitov I., Kiziloǧlu U., Klunko E., Kubánek P., Kutyrev A., Laursen P., Levan A., Mannucci F., Martin C., Mescheryakov A., Mirabal N., Norris J., Ovaldsen J., Paraficz D., Pavlenko E., Piranomonte S., Rossi A., Rumyantsev V., Salinas R., Sergeev A., Sharapov D., Sollerman J., Stecklum B., Stella L., Tagliaferri G., Tanvir N., Telting J., Testa V., Updike A., Volnova A., Watson D., Wiersema K., Xu D., Kann D., Klose S., Zhang B., Malesani D., Nakar E., Pozanenko A., Wilson A., Butler N., Jakobsson P., Schulze S., Andreev M., Antonelli L., Bikmaev I., Biryukov V., Böttcher M., Burenin R., Cerón J., Castro-Tirado A., Chincarini G., Cobb B., Covino S., D'Avanzo P., D'Elia V., Valle M., De Ugarte Postigo A., Efimov Y., Ferrero P., Fugazza D., Fynbo J., Gålfalk M., Grundahl F., Gorosabel J., Gupta S., Guziy S., Hafizov B., Hjorth J., Holhjem K., Ibrahimov M., Im M., Israel G., Jelainek M., Jensen B., Karimov R., Khamitov I., Kiziloǧlu U., Klunko E., Kubánek P., Kutyrev A., Laursen P., Levan A., Mannucci F., Martin C., Mescheryakov A., Mirabal N., Norris J., Ovaldsen J., Paraficz D., Pavlenko E., Piranomonte S., Rossi A., Rumyantsev V., Salinas R., Sergeev A., Sharapov D., Sollerman J., Stecklum B., Stella L., Tagliaferri G., Tanvir N., Telting J., Testa V., Updike A., Volnova A., Watson D., Wiersema K., and Xu D.

Abstract

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing us to estimate the host-galaxy extinction. We transformed the afterglow light curves into an extinction-corrected z = 1 system and compared their luminosities with a sample of pre-Swift afterglows. The results of a former study, which showed that GRB afterglows clustered and exhibited a bimodal distribution in luminosity space, are weakened by the larger sample. We found that the luminosity distribution of the two afterglow samples (Swift-era and pre-Swift) is very similar, and that a subsample for which we were not able to estimate the extinction, which is fainter than the main sample, can be explained by assuming a moderate amount of line-of-sight host extinction. We derived bolometric isotropic energies for all GRBs in our sample, and found only a tentative correlation between the prompt energy release and the optical afterglow luminosity at 1 day after the GRB in the z = 1 system. A comparative study of the optical luminosities of GRB afterglows with echelle spectra (which show a high number of foreground absorbing systems) and those without, reveals no indication that the former are statistically significantly more luminous. Furthermore, we propose the existence of an upper ceiling on afterglow luminosities and study the luminosity distribution at early times, which was not accessible before the advent of the Swift satellite. Most GRBs feature aftergl

314. The afterglows of Swift-era gamma-ray bursts. I. Comparing pre-Swift and Swift-era long/soft (type II) GRB optical afterglows

Author

Kann D., Klose S., Zhang B., Malesani D., Nakar E., Pozanenko A., Wilson A., Butler N., Jakobsson P., Schulze S., Andreev M., Antonelli L., Bikmaev I., Biryukov V., Böttcher M., Burenin R., Cerón J., Castro-Tirado A., Chincarini G., Cobb B., Covino S., D'Avanzo P., D'Elia V., Valle M., De Ugarte Postigo A., Efimov Y., Ferrero P., Fugazza D., Fynbo J., Gålfalk M., Grundahl F., Gorosabel J., Gupta S., Guziy S., Hafizov B., Hjorth J., Holhjem K., Ibrahimov M., Im M., Israel G., Jelainek M., Jensen B., Karimov R., Khamitov I., Kiziloǧlu U., Klunko E., Kubánek P., Kutyrev A., Laursen P., Levan A., Mannucci F., Martin C., Mescheryakov A., Mirabal N., Norris J., Ovaldsen J., Paraficz D., Pavlenko E., Piranomonte S., Rossi A., Rumyantsev V., Salinas R., Sergeev A., Sharapov D., Sollerman J., Stecklum B., Stella L., Tagliaferri G., Tanvir N., Telting J., Testa V., Updike A., Volnova A., Watson D., Wiersema K., Xu D., Kann D., Klose S., Zhang B., Malesani D., Nakar E., Pozanenko A., Wilson A., Butler N., Jakobsson P., Schulze S., Andreev M., Antonelli L., Bikmaev I., Biryukov V., Böttcher M., Burenin R., Cerón J., Castro-Tirado A., Chincarini G., Cobb B., Covino S., D'Avanzo P., D'Elia V., Valle M., De Ugarte Postigo A., Efimov Y., Ferrero P., Fugazza D., Fynbo J., Gålfalk M., Grundahl F., Gorosabel J., Gupta S., Guziy S., Hafizov B., Hjorth J., Holhjem K., Ibrahimov M., Im M., Israel G., Jelainek M., Jensen B., Karimov R., Khamitov I., Kiziloǧlu U., Klunko E., Kubánek P., Kutyrev A., Laursen P., Levan A., Mannucci F., Martin C., Mescheryakov A., Mirabal N., Norris J., Ovaldsen J., Paraficz D., Pavlenko E., Piranomonte S., Rossi A., Rumyantsev V., Salinas R., Sergeev A., Sharapov D., Sollerman J., Stecklum B., Stella L., Tagliaferri G., Tanvir N., Telting J., Testa V., Updike A., Volnova A., Watson D., Wiersema K., and Xu D.

Abstract

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing us to estimate the host-galaxy extinction. We transformed the afterglow light curves into an extinction-corrected z = 1 system and compared their luminosities with a sample of pre-Swift afterglows. The results of a former study, which showed that GRB afterglows clustered and exhibited a bimodal distribution in luminosity space, are weakened by the larger sample. We found that the luminosity distribution of the two afterglow samples (Swift-era and pre-Swift) is very similar, and that a subsample for which we were not able to estimate the extinction, which is fainter than the main sample, can be explained by assuming a moderate amount of line-of-sight host extinction. We derived bolometric isotropic energies for all GRBs in our sample, and found only a tentative correlation between the prompt energy release and the optical afterglow luminosity at 1 day after the GRB in the z = 1 system. A comparative study of the optical luminosities of GRB afterglows with echelle spectra (which show a high number of foreground absorbing systems) and those without, reveals no indication that the former are statistically significantly more luminous. Furthermore, we propose the existence of an upper ceiling on afterglow luminosities and study the luminosity distribution at early times, which was not accessible before the advent of the Swift satellite. Most GRBs feature aftergl

315. THE AFTERGLOWS OF SWIFT-ERA GAMMA-RAY BURSTS. I. COMPARING PRE-SWIFT AND SWIFT-ERA LONG/SOFT (TYPE II) GRB OPTICAL AFTERGLOWS

Author

Kann, D. A., Klose, S., Zhang, B., Malesani, D., Nakar, E., Pozanenko, A., Wilson, A. C., Butler, N. R., Jakobsson, P., Schulze, S., Andreev, M., Antonelli, L. A., Bikmaev, I. F., Biryukov, V., B¨ottcher, M., Burenin, R. A., Castro Cer´on, J. M., Castro-Tirado, A. J., Chincarini, G., Cobb, B. E., Covino, S., D’Avanzo, P., D’Elia, V., Della Valle, M., de Ugarte Postigo, A., Efimov, Yu, Ferrero, P., Fugazza, D., Fynbo, J. P.U., Gålfalk, M., Grundahl, F., Gorosabel, J., Gupta, S., Guziy, S., Hafizov, B., Hjorth, J., Holhjem, K., Ibrahimov, M., Im, M., Israel, G. L., Je´linek, M., Jensen, B. L., Karimov, R., Khamitov, I. M., Kizilogˇlu, U., Klunko, E., Kuba´nek, P., Kutyrev, A. S., Laursen, P., Levan, A. J., Mannucci, F., Martin, C. M., Mescheryakov, A., Mirabal, N., Norris, J. P., Ovaldsen, J. -E., Paraficz, D., Pavlenko, E., Piranomonte, S., Rossi, A., Rumyantsev, V., Salinas, R., Sergeev, A., Sharapov, D., Sollerman, J., Stecklum, B., Stella, L., Tagliaferri, G., Tanvir, N. R., Telting, J., Testa, V., Updike, Adria, Volnova, A., Watson, D., Wiersema, K., Xu, D., Kann, D. A., Klose, S., Zhang, B., Malesani, D., Nakar, E., Pozanenko, A., Wilson, A. C., Butler, N. R., Jakobsson, P., Schulze, S., Andreev, M., Antonelli, L. A., Bikmaev, I. F., Biryukov, V., B¨ottcher, M., Burenin, R. A., Castro Cer´on, J. M., Castro-Tirado, A. J., Chincarini, G., Cobb, B. E., Covino, S., D’Avanzo, P., D’Elia, V., Della Valle, M., de Ugarte Postigo, A., Efimov, Yu, Ferrero, P., Fugazza, D., Fynbo, J. P.U., Gålfalk, M., Grundahl, F., Gorosabel, J., Gupta, S., Guziy, S., Hafizov, B., Hjorth, J., Holhjem, K., Ibrahimov, M., Im, M., Israel, G. L., Je´linek, M., Jensen, B. L., Karimov, R., Khamitov, I. M., Kizilogˇlu, U., Klunko, E., Kuba´nek, P., Kutyrev, A. S., Laursen, P., Levan, A. J., Mannucci, F., Martin, C. M., Mescheryakov, A., Mirabal, N., Norris, J. P., Ovaldsen, J. -E., Paraficz, D., Pavlenko, E., Piranomonte, S., Rossi, A., Rumyantsev, V., Salinas, R., Sergeev, A., Sharapov, D., Sollerman, J., Stecklum, B., Stella, L., Tagliaferri, G., Tanvir, N. R., Telting, J., Testa, V., Updike, Adria, Volnova, A., Watson, D., Wiersema, K., and Xu, D.

Abstract

Published in: Astrophysical Journal, Volume 720, 2010

316. THE AFTERGLOWS OF SWIFT-ERA GAMMA-RAY BURSTS. I. COMPARING PRE-SWIFT AND SWIFT-ERA LONG/SOFT (TYPE II) GRB OPTICAL AFTERGLOWS

Author

Kann, D. A., Klose, S., Zhang, B., Malesani, D., Nakar, E., Pozanenko, A., Wilson, A. C., Butler, N. R., Jakobsson, P., Schulze, S., Andreev, M., Antonelli, L. A., Bikmaev, I. F., Biryukov, V., B¨ottcher, M., Burenin, R. A., Castro Cer´on, J. M., Castro-Tirado, A. J., Chincarini, G., Cobb, B. E., Covino, S., D’Avanzo, P., D’Elia, V., Della Valle, M., de Ugarte Postigo, A., Efimov, Yu, Ferrero, P., Fugazza, D., Fynbo, J. P.U., Gålfalk, M., Grundahl, F., Gorosabel, J., Gupta, S., Guziy, S., Hafizov, B., Hjorth, J., Holhjem, K., Ibrahimov, M., Im, M., Israel, G. L., Je´linek, M., Jensen, B. L., Karimov, R., Khamitov, I. M., Kizilogˇlu, U., Klunko, E., Kuba´nek, P., Kutyrev, A. S., Laursen, P., Levan, A. J., Mannucci, F., Martin, C. M., Mescheryakov, A., Mirabal, N., Norris, J. P., Ovaldsen, J. -E., Paraficz, D., Pavlenko, E., Piranomonte, S., Rossi, A., Rumyantsev, V., Salinas, R., Sergeev, A., Sharapov, D., Sollerman, J., Stecklum, B., Stella, L., Tagliaferri, G., Tanvir, N. R., Telting, J., Testa, V., Updike, Adria, Volnova, A., Watson, D., Wiersema, K., Xu, D., Kann, D. A., Klose, S., Zhang, B., Malesani, D., Nakar, E., Pozanenko, A., Wilson, A. C., Butler, N. R., Jakobsson, P., Schulze, S., Andreev, M., Antonelli, L. A., Bikmaev, I. F., Biryukov, V., B¨ottcher, M., Burenin, R. A., Castro Cer´on, J. M., Castro-Tirado, A. J., Chincarini, G., Cobb, B. E., Covino, S., D’Avanzo, P., D’Elia, V., Della Valle, M., de Ugarte Postigo, A., Efimov, Yu, Ferrero, P., Fugazza, D., Fynbo, J. P.U., Gålfalk, M., Grundahl, F., Gorosabel, J., Gupta, S., Guziy, S., Hafizov, B., Hjorth, J., Holhjem, K., Ibrahimov, M., Im, M., Israel, G. L., Je´linek, M., Jensen, B. L., Karimov, R., Khamitov, I. M., Kizilogˇlu, U., Klunko, E., Kuba´nek, P., Kutyrev, A. S., Laursen, P., Levan, A. J., Mannucci, F., Martin, C. M., Mescheryakov, A., Mirabal, N., Norris, J. P., Ovaldsen, J. -E., Paraficz, D., Pavlenko, E., Piranomonte, S., Rossi, A., Rumyantsev, V., Salinas, R., Sergeev, A., Sharapov, D., Sollerman, J., Stecklum, B., Stella, L., Tagliaferri, G., Tanvir, N. R., Telting, J., Testa, V., Updike, Adria, Volnova, A., Watson, D., Wiersema, K., and Xu, D.

Abstract

Published in: Astrophysical Journal, Volume 720, 2010

318. A Simultaneous X-Ray and Optical Study of TT Arietis

Author

Hudec, R., primary, Valníček, B., additional, Peřesty, R., additional, Wenzel, W., additional, Richter, G.A., additional, Goetz, W., additional, Hacke, G., additional, Huth, H., additional, Schult, R., additional, Pfau, W., additional, Reimann, G.-H., additional, Stecklum, B., additional, Tremko, J., additional, Mrkos, A., additional, Schpitshka, I.V., additional, Kojevnikov, V.P., additional, Kumshiashvili, M.I., additional, Oprescu, G., additional, Dumitrescu, A., additional, Cristescu, C., additional, Bojack, W., additional, Patkós, L., additional, Toth, I., additional, and Oláh, K., additional

Published
1987
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320. SOFIA confirms an accretion burst from a massive young stellar object

Author

Stecklum, B., Wolf, V., Linz, H., Caratti o Garatti, A., Schmidl, S., Klose, S., Eislöffel, J., Fischer, Ch., Brogan, C., Burns, R. A., Bayandina, O., Cyganowski, C., Gurwell, M., Hunter, T., Hirano, N., Kim, K.-T., MacLeod, G., Menten, K. M., Olech, M., Orosz, G., Sobolev, A., Sridharan, T. K., Surcis, G., Sugiyama, K., van der Walt, J., Volvach, A., and Yonekura, Y.

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325. Transiting exoplanets from the CoRoT space mission

Author

Gandolfi, D., Hébrard, G., Alonso, R., Deleuil, M., Guenther, E. W., Fridlund, M., Endl, M., Eigmüller, P., Csizmadia, Sz., Havel, M., Aigrain, S., Auvergne, M., Baglin, A., Barge, P., Bonomo, A. S., Bordé, P., Bouchy, F., Bruntt, H., Cabrera, J., Carpano, S., Carone, L., Cochran, W. D., Deeg, H. J., Dvorak, R., Eislöffel, J., Erikson, A., Ferraz-Mello, S., Gazzano, J.-C., Gibson, N. B., Gillon, M., Gondoin, P., Guillot, T., Hartmann, M., Hatzes, A., Jorda, L., Kabath, P., Léger, A., Llebaria, A., Lammer, H., MacQueen, P. J., Mayor, M., Mazeh, T., Moutou, C., Ollivier, M., Pätzold, M., Pepe, F., Queloz, D., Rauer, H., Rouan, D., Samuel, B., Schneider, J., Stecklum, B., Tingley, B., Udry, S., and Wuchterl, G.

Abstract

The CoRoTexoplanet science team announces the discovery of CoRoT-11b, a fairly massive hot-Jupiter transiting a V= 12.9 mag F6 dwarf star (M∗= 1.27 ± 0.05 M⊙, R∗= 1.37 ± 0.03 R⊙, Teff= 6440 ± 120 K), with an orbital period of P= 2.994329 ± 0.000011 days and semi-major axis a= 0.0436 ± 0.005 AU. The detection of part of the radial velocity anomaly caused by the Rossiter-McLaughlin effect shows that the transit-like events detected by CoRoTare caused by a planet-sized transiting object in a prograde orbit. The relatively high projected rotational velocity of the star (vsini⋆= 40 ± 5 km s-1) places CoRoT-11 among the most rapidly rotating planet host stars discovered so far. With a planetary mass of Mp= 2.33 ± 0.34 MJupand radius Rp= 1.43 ± 0.03 RJup, the resulting mean density of CoRoT-11b (ρp= 0.99 ± 0.15 g/cm3) can be explained with a model for an inflated hydrogen-planet with a solar composition and a high level of energy dissipation in its interior.

Published
2010
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327. 739 observed NEAs and new 2–4m survey statistics within the EURONEAR network.

Author

Vaduvescu, O., Birlan, M., Tudorica, A., Popescu, M., Colas, F., Asher, D.J., Sonka, A., Suciu, O., Lacatus, D., Paraschiv, A., Badescu, T., Tercu, O., Dumitriu, A., Chirila, A., Stecklum, B., Licandro, J., Nedelcu, A., Turcu, E., Vachier, F., and Beauvalet, L.

Subjects
*ASTRONOMY, *ASTROMETRY, *ASTROMETRIC telescopes, *SPACE sciences, *SQUARE, *MANAGEMENT science, *STATISTICS
Abstract

Abstract: We report follow-up observations of 477 program Near-Earth Asteroids (NEAs) using nine telescopes of the EURONEAR network having apertures between 0.3 and 4.2m. Adding these NEAs to our previous results we now count 739 program NEAs followed-up by the EURONEAR network since 2006. The targets were selected using EURONEAR planning tools focusing on high priority objects. Analyzing the resulting orbital improvements suggests astrometric follow-up is most important days to weeks after discovery, with recovery at a new opposition also valuable. Additionally we observed 40 survey fields spanning three nights covering 11 square degrees near opposition, using the Wide Field Camera on the 2.5m Isaac Newton Telescope (INT), resulting in 104 discovered main belt asteroids (MBAs) and another 626 unknown one-night objects. These fields, plus program NEA fields from the INT and from the wide field MOSAIC II camera on the Blanco 4m telescope, generated around 12000 observations of 2000 minor planets (mostly MBAs) observed in 34 square degrees. We identify Near Earth Object (NEO) candidates among the unknown (single night) objects using three selection criteria. Testing these criteria on the (known) program NEAs shows that the best selection method is our model which checks solar elongation and sky motion and the MPC's NEO rating tool. Our new data show that on average 0.5 NEO candidates per square degree should be observable in a 2m-class survey (in agreement with past results), while an average of 2.7 NEO candidates per square degree should be observable in a 4m-class survey (although our Blanco statistics were affected by clouds). At opposition just over 100 MBAs (1.6 unknown to every 1 known) per square degree are detectable to R=22 in a 2m survey based on the INT data (in accordance with other results), while our two best ecliptic Blanco fields away from opposition lead to 135 MBAs (2 unknown to every 1 known) to R=23. [Copyright &y& Elsevier]

Published
2013
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328. UWISH2 - the UKIRT Widefield Infrared Survey for H2.

Author

Froebrich, D., Davis, C. J., Ioannidis, G., Gledhill, T. M., Takami, M., Chrysostomou, A., Drew, J., Eislöffel, J., Gosling, A., Gredel, R., Hatchell, J., Hodapp, K. W., Kumar, M. S. N., Lucas, P. W., Matthews, H., Rawlings, M. G., Smith, M. D., Stecklum, B., Varricatt, W. P., and Lee, H. T.

Subjects
*INFRARED imaging, *MOLECULAR clouds, *STAR formation, *SUPERNOVA remnants, *ASTRONOMICAL photometry, *ENERGY bands
Abstract

ABSTRACT We present the goals and preliminary results of an unbiased, near-infrared, narrow-band imaging survey of the first galactic quadrant (10° < l < 65°; −13 < b < +13). This area includes most of the giant molecular clouds and massive star forming regions in the Northern hemisphere. The survey is centred on the 1-0 S(1) rovibrational line of H 2, a proven tracer of hot, dense molecular gas in star-forming regions, around evolved stars, and in supernova remnants. The observations complement existing and upcoming photometric surveys ( Spitzer-GLIMPSE, UKIDSS-GPS, JCMT-JPS, AKARI, Herschel Hi-GAL, etc.), though we probe a dynamically active component of star formation not covered by these broad-band surveys. Our narrow-band survey is currently more than 60 per cent complete. The median seeing in our images is 0.73 arcsec. The images have a 5 σ detection limit of point sources of K∼ 18 mag and the surface brightness limit is 10 −19 W m −2 arcsec −2 when averaged over our typical seeing. Jets and outflows from both low- and high-mass young stellar objects are revealed, as are new planetary nebulae and - via a comparison with earlier K-band observations acquired as a part of the UKIDSS GPS - numerous variable stars. With their superior spatial resolution, the UWISH2 data also have the potential to reveal the true nature of many of the extended green objects found in the GLIMPSE survey. [ABSTRACT FROM AUTHOR]

Published
2011
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329. Kilometer-range nonlinear propagation of femtosecond laser pulses.

Author

Rodriguez M, Bourayou R, Méjean G, Kasparian J, Yu J, Salmon E, Scholz A, Stecklum B, Eislöffel J, Laux U, Hatzes AP, Sauerbrey R, Wöste L, and Wolf JP

Abstract

Ultrashort, high-power laser pulses propagating vertically in the atmosphere have been observed over more than 20 km using an imaging 2-m astronomical telescope. This direct observation in several wavelength bands shows indications for filament formation at distances as far as 2 km in the atmosphere. Moreover, the beam divergence at 5 km altitude is smaller than expected, bearing evidence for whole-beam parallelization about the nonlinear focus. We discuss implications for white-light Lidar applications.

Published
2004
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330. Evolution of the polarization of the optical afterglow of the gamma-ray burst GRB030329.

Author

Greiner J, Klose S, Reinsch K, Schmid HM, Sari R, Hartmann DH, Kouveliotou C, Rau A, Palazzi E, Straubmeier C, Stecklum B, Zharikov S, Tovmassian G, Bärnbantner O, Ries C, Jehin E, Henden A, Kaas AA, Grav T, Hjorth J, Pedersen H, Wijers RA, Kaufer A, Park HS, Williams G, and Reimer O

Abstract

The association of a supernova with GRB030329 strongly supports the 'collapsar' model of gamma-ray bursts, where a relativistic jet forms after the progenitor star collapses. Such jets cannot be spatially resolved because gamma-ray bursts lie at cosmological distances; their existence is instead inferred from 'breaks' in the light curves of the afterglows, and from the theoretical desire to reduce the estimated total energy of the burst by proposing that most of it comes out in narrow beams. Temporal evolution of the polarization of the afterglows may provide independent evidence for the jet structure of the relativistic outflow. Small-level polarization ( approximately 1-3 per cent) has been reported for a few bursts, but its temporal evolution has yet to be established. Here we report polarimetric observations of the afterglow of GRB030329. We establish the polarization light curve, detect sustained polarization at the per cent level, and find significant variability. The data imply that the afterglow magnetic field has a small coherence length and is mostly random, probably generated by turbulence, in contrast with the picture arising from the high polarization detected in the prompt gamma-rays from GRB021206 (ref. 18).

Published
2003
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