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1. The TRAPUM Large Magellanic Cloud pulsar survey with MeerKAT I: Survey setup and first seven pulsar discoveries

Author

Prayag, V., Levin, L., Geyer, M., Stappers, B. W., Carli, E., Barr, E. D., Breton, R. P., Buchner, S., Burgay, M., Kramer, M., Possenti, A., Krishnan, V. Venkatraman, Venter, C., Behrend, J., Chen, W., Horn, D. M., Padmanabh, P. V., and Ridolfi, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The Large Magellanic Cloud (LMC) presents a unique environment for pulsar population studies due to its distinct star formation characteristics and proximity to the Milky Way. As part of the TRAPUM (TRAnsients and PUlsars with MeerKAT) Large Survey Project, we are using the core array of the MeerKAT radio telescope (MeerKAT) to conduct a targeted search of the LMC for radio pulsars at L-band frequencies, 856-1712$\,$MHz. The excellent sensitivity of MeerKAT, coupled with a 2-hour integration time, makes the survey 3 times more sensitive than previous LMC radio pulsar surveys. We report the results from the initial four survey pointings which has resulted in the discovery of seven new radio pulsars, increasing the LMC radio pulsar population by 30 per cent. The pulse periods of these new pulsars range from 278 to 1690$\,$ms, and the highest dispersion measure is 254.20$\,$pc$\,$cm$^{-3}$. We searched for, but did not find any significant pulsed radio emission in a beam centred on the SN$\,$1987A remnant, establishing an upper limit of 6.3$\,{\mu}$Jy on its minimum flux density at 1400$\,$MHz., Comment: 12 pages, 4 figures, 4 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society

Published
2024
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2. The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT: I. Discovery of seven new pulsars and two Pulsar Wind Nebula associations

Author

Carli, E., Levin, L., Stappers, B. W., Barr, E. D., Breton, R. P., Buchner, S., Burgay, M., Geyer, M., Kramer, M., Padmanabh, P. V., Possenti, A., Krishnan, V. Venkatraman, Becker, W., Filipović, M. D., Maitra, C., Behrend, J., Champion, D. J., Chen, W., Men, Y. P., and Ridolfi, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract

The sensitivity of the MeerKAT radio interferometer is an opportunity to probe deeper into the population of rare and faint extragalactic pulsars. The TRAPUM (TRAnsients and PUlsars with MeerKAT) collaboration has conducted a radio-domain search for accelerated pulsars and transients in the Small Magellanic Cloud (SMC). This partially targeted survey, performed at L-band (856-1712 MHz) with the core array of the MeerKAT telescope in 2-h integrations, is twice as sensitive as the latest SMC radio pulsar survey. We report the discovery of seven new SMC pulsars, doubling this galaxy's radio pulsar population and increasing the total extragalactic population by nearly a quarter. We also carried out a search for accelerated millisecond pulsars in the SMC Globular Cluster NGC 121 using the full array of MeerKAT. This improved the previous upper limit on pulsed radio emission from this cluster by a factor of six. Our discoveries reveal the first radio pulsar-PWN systems in the SMC, with only one such system previously known outside our galaxy (the "Crab pulsar twin" in the Large Magellanic Cloud, PSR J0540$-$6919). We associate the 59 ms pulsar discovery PSR J0040$-$7337, now the fastest spinning radio pulsar in the SMC, with the bow-shock Pulsar Wind Nebula (PWN) of Supernova Remnant DEM S5. We also present a new young pulsar with a 79 ms period, PSR J0048$-$7317, in a PWN recently discovered in a MeerKAT radio continuum image. Using the multi-beam capability of MeerKAT, we localised our pulsar discoveries, and two previous Murriyang discoveries, to a positional uncertainty of a few arcseconds., Comment: 32 pages, 14 figures, 10 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society

Published
2024
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3. TRAPUM search for pulsars in supernova remnants and pulsar wind nebulae -- I. Survey description and initial discoveries

Author

Turner, J. D., Stappers, B. W., Carli, E., Barr, E. D., Becker, W., Behrend, J., Breton, R. P., Buchner, S., Burgay, M., Champion, D. J., Chen, W., Clark, C. J., Horn, D. M., Keane, E. F., Kramer, M., ünkel, L. K, Levin, L., Men, Y. P., Padmanabh, P. V., Ridolfi, A., and Krishnan, V. Venkatraman

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present the description and initial results of the TRAPUM (TRAnsients And PUlsars with MeerKAT) search for pulsars associated with supernova remnants (SNRs), pulsar wind nebulae and unidentified TeV emission. The list of sources to be targeted includes a large number of well-known candidate pulsar locations but also new candidate SNRs identified using a range of criteria. Using the 64-dish MeerKAT radio telescope, we use an interferometric beamforming technique to tile the potential pulsar locations with coherent beams which we search for radio pulsations, above a signal-to-noise of 9, down to an average flux density upper limit of 30 $\mu$Jy. This limit is target-dependent due to the contribution of the sky and nebula to the system temperature. Coherent beams are arranged to overlap at their 50 per cent power radius, so the sensitivity to pulsars is not degraded by more than this amount, though realistically averages around 65 per cent if every location in the beam is considered. We report the discovery of two new pulsars; PSR J1831$-$0941 is an adolescent pulsar likely to be the plerionic engine of the candidate PWN G20.0+0.0, and PSR J1818$-$1502 appears to be an old and faint pulsar that we serendipitously discovered near the centre of a SNR already hosting a compact central object. The survey holds importance for better understanding of neutron star birth rates and the energetics of young pulsars., Comment: 17 pages, 6 figures, 3 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society

Published
2024
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4. The TRAPUM L-band survey for pulsars in Fermi-LAT gamma-ray sources

Author

Clark, C. J., Breton, R. P., Barr, E. D., Burgay, M., Thongmeearkom, T., Nieder, L., Buchner, S., Stappers, B., Kramer, M., Becker, W., Mayer, M., Phosrisom, A., Ashok, A., Bezuidenhout, M. C., Calore, F., Cognard, I., Freire, P. C. C., Geyer, M., Grießmeier, J. -M., Karuppusamy, R., Levin, L., Padmanabh, P. V., Possenti, A., Ransom, S., Serylak, M., Krishnan, V. Venkatraman, Vleeschower, L., Behrend, J., Champion, D. J., Chen, W., Horn, D., Keane, E. F., Künkel, L., Men, Y., Ridolfi, A., Dhillon, V. S., Marsh, T. R., and Papa, M. A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

More than 100 millisecond pulsars (MSPs) have been discovered in radio observations of gamma-ray sources detected by the Fermi Large Area Telescope (LAT), but hundreds of pulsar-like sources remain unidentified. Here we present the first results from the targeted survey of Fermi-LAT sources being performed by the Transients and Pulsars with MeerKAT (TRAPUM) Large Survey Project. We observed 79 sources identified as possible gamma-ray pulsar candidates by a Random Forest classification of unassociated sources from the 4FGL catalogue. Each source was observed for 10 minutes on two separate epochs using MeerKAT's L-band receiver (856-1712 MHz), with typical pulsed flux density sensitivities of $\sim$100$\,\mu$Jy. Nine new MSPs were discovered, eight of which are in binary systems, including two eclipsing redbacks and one system, PSR J1526$-$2744, that appears to have a white dwarf companion in an unusually compact 5 hr orbit. We obtained phase-connected timing solutions for two of these MSPs, enabling the detection of gamma-ray pulsations in the Fermi-LAT data. A follow-up search for continuous gravitational waves from PSR J1526$-$2744 in Advanced LIGO data using the resulting Fermi-LAT timing ephemeris yielded no detection, but sets an upper limit on the neutron star ellipticity of $2.45\times10^{-8}$. We also detected X-ray emission from the redback PSR J1803$-$6707 in data from the first eROSITA all-sky survey, likely due to emission from an intra-binary shock., Comment: 17 pages, 8 figures, accepted for publication in MNRAS

Published
2022
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5. TRAPUM upper limits on pulsed radio emission for SMC X-ray pulsar J0058-7218

Author

Carli, E., Levin, L., Stappers, B. W., Barr, E. D., Breton, R. P., Buchner, S., Burgay, M., Kramer, M., Padmanabh, P. V., Possenti, A., Krishnan, V. Venkatraman, Behrend, J., Champion, D. J., Chen, W., and Men, Y. P.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The TRAPUM collaboration has used the MeerKAT telescope to conduct a search for pulsed radio emission from the young Small Magellanic Cloud pulsar J0058-7218 located in the supernova remnant IKT 16, following its discovery in X-rays with XMM-Newton. We report no significant detection of dispersed, pulsed radio emission from this source in three 2-hour L-band observations using the core dishes of MeerKAT, setting an upper limit of 7.0 {\mu}Jy on its mean flux density at 1284 MHz. This is nearly 7 times deeper than previous radio searches for this pulsar in Parkes L-band observations. This suggests that the radio emission of PSR J0058-7218 is not beamed towards Earth or that PSR J0058-7218 is similar to a handful of Pulsar Wind Nebulae systems that have a very low radio efficiency, such as PSR B0540-6919, the Large Magellanic Cloud Crab pulsar analogue. We have also searched for bright, dispersed, single radio pulses and found no candidates above a fluence of 93 mJy ms at 1284 MHz., Comment: 7 pages, 2 figures, 1 table. Accepted for publication in Monthly Notices of the Royal Astronomical Society

Published
2022
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6. A burst storm from the repeating FRB 20200120E in an M81 globular cluster

Author

Nimmo, K., Hessels, J. W. T., Snelders, M. P., Karuppusamy, R., Hewitt, D. M., Kirsten, F., Marcote, B., Bach, U., Bansod, A., Barr, E. D., Behrend, J., Bezrukovs, V., Buttaccio, S., Feiler, R., Gawroński, M. P., Lindqvist, M., Orbidans, A., Puchalska, W., Wang, N., Winchen, T., Wolak, P., Wu, J., and Yuan, J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The repeating fast radio burst (FRB) source FRB 20200120E is exceptional because of its proximity and association with a globular cluster. Here we report $60$ bursts detected with the Effelsberg telescope at 1.4 GHz. We observe large variations in the burst rate, and report the first FRB 20200120E `burst storm', where the source suddenly became active and 53 bursts (fluence $\geq 0.04$ Jy ms) occurred within only 40 minutes. We find no strict periodicity in the burst arrival times, nor any evidence for periodicity in the source's activity between observations. The burst storm shows a steep energy distribution (power-law index $\alpha = 2.39\pm0.12$) and a bi-modal wait-time distribution, with log-normal means of 0.94$^{+0.07}_{-0.06}$ s and 23.61$^{+3.06}_{-2.71}$ s. We attribute these wait-time distribution peaks to a characteristic event timescale and pseudo-Poisson burst rate, respectively. The secondary wait-time peak at $\sim1$ s is $\sim50\times$ longer than the $\sim24$ ms timescale seen for both FRB 20121102A and FRB 20201124A -- potentially indicating a larger emission region, or slower burst propagation. FRB 20200120E shows order-of-magnitude lower burst durations and luminosities compared with FRB 20121102A and FRB 20201124A. Lastly, in contrast to FRB 20121102A, which has observed dispersion measure (DM) variations of $\Delta{\rm DM} >1$ pc cm$^{-3}$ on month-to-year timescales, we determine that FRB 20200120E's DM has remained stable ($\Delta{\rm DM} <0.15$ pc cm$^{-3}$) over $>10$ months. Overall, the observational characteristics of FRB 20200120E deviate quantitatively from other active repeaters, but it is unclear whether it is qualitatively a different type of source., Comment: Accepted for publication in MNRAS

Published
2022
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7. Four pulsar discoveries in NGC 6624 by TRAPUM using MeerKAT

Author

Abbate, F., Ridolfi, A., Barr, E. D., Buchner, S., Burgay, M., Champion, D. J., Chen, W., Freire, P. C. C., Gautam, T., Grießmeier, J. M., Künkel, L., Kramer, M., Padmanabh, P. V., Possenti, A., Ransom, S., Serylak, M., Stappers, B. W., Krishnan, V. Venkatraman, Behrend, J., Breton, R. P., Levin, L., and Men, Y.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We report 4 new pulsars discovered in the core-collapsed globular cluster (GC) NGC 6624 by the TRAPUM Large Survey Project with the MeerKAT telescope. All of the new pulsars found are isolated. PSR J1823$-$3021I and PSR J1823$-$3021K are millisecond pulsars with period of respectively 4.319 ms and 2.768 ms. PSR J1823$-$3021J is mildly recycled with a period of 20.899 ms, and PSR J1823$-$3022 is a long period pulsar with a period of 2.497 s. The pulsars J1823$-$3021I, J1823$-$3021J, and J1823$-$3021K have position and dispersion measure (DM) compatible with being members of the GC and are therefore associated with NGC 6624. Pulsar J1823$-$3022 is the only pulsar bright enough to be re-detected in archival observations of the cluster. This allowed the determination of a timing solution that spans over two decades. It is not possible at the moment to claim the association of pulsar J1823$-$3022 with the GC given the long period and large offset in position ($\sim 3$ arcminutes) and DM (with a fractional difference of 11 percent compared the average of the pulsars in NGC 6624). The discoveries made use of the beamforming capability of the TRAPUM backend to generate multiple beams in the same field of view which allows sensitive searches to be performed over a few half-light radii from the cluster center and can simultaneously localise the discoveries. The discoveries reflect the properties expected for pulsars in core-collapsed GCs., Comment: Accepted for publication on Monthly Notices of the Royal Astronomical Society. 11 pages, 6 figures

Published
2022
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8. The TRAPUM large magellanic cloud pulsar survey with MeerKAT I: survey set-up and first seven pulsar discoveries.

Author

Prayag, V, Levin, L, Geyer, M, Stappers, B W, Carli, E, Barr, E D, Breton, R P, Buchner, S, Burgay, M, Kramer, M, Possenti, A, Krishnan, V Venkatraman, Venter, C, Behrend, J, Chen, W, Horn, D M, Padmanabh, P V, and Ridolfi, A

Subjects
LARGE magellanic cloud, MAGELLANIC clouds, PULSAR detection, RADIO telescopes, MILKY Way
Abstract

The Large Magellanic Cloud (LMC) presents a unique environment for pulsar population studies due to its distinct star formation characteristics and proximity to the Milky Way. As part of the TRAPUM (TRAnsients and PUlsars with MeerKAT) Large Survey Project, we are using the core array of the MeerKAT radio telescope (MeerKAT) to conduct a targeted search of the LMC for radio pulsars at L -band frequencies, 856–1712 MHz. The excellent sensitivity of MeerKAT, coupled with a 2-h integration time, makes the survey 3 times more sensitive than previous LMC radio pulsar surveys. We report the results from the initial four survey pointings which have resulted in the discovery of seven new radio pulsars, increasing the LMC radio pulsar population by 30 per cent. The pulse periods of these new pulsars range from 278 to 1690 ms, and the highest dispersion measure is 254.20  |$\mathrm{ pc} \, \mathrm{ cm}^{-3}$|⁠. We searched for, but did not find any significant pulsed radio emission in a beam centred on the SN 1987A remnant, establishing an upper limit of 6.3  |$\mu \mathrm{ Jy}$| on its minimum flux density at 1400 MHz. [ABSTRACT FROM AUTHOR]

Published
2024
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9. The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT:I. Discovery of seven new pulsars and two Pulsar Wind Nebula associations

Author

Carli, E, primary, Levin, L, additional, Stappers, B W, additional, Barr, E D, additional, Breton, R P, additional, Buchner, S, additional, Burgay, M, additional, Geyer, M, additional, Kramer, M, additional, Padmanabh, P V, additional, Possenti, A, additional, Krishnan, V Venkatraman, additional, Becker, W, additional, Filipović, M D, additional, Maitra, C, additional, Behrend, J, additional, Champion, D J, additional, Chen, W, additional, Men, Y P, additional, and Ridolfi, A, additional

Published
2024
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10. TRAPUM search for pulsars in supernova remnants and pulsar wind nebulae − I. Survey description and initial discoveries

Author

Turner, J D, primary, Stappers, B W, additional, Carli, E, additional, Barr, E D, additional, Becker, W, additional, Behrend, J, additional, Breton, R P, additional, Buchner, S, additional, Burgay, M, additional, Champion, D J, additional, Chen, W, additional, Clark, C J, additional, Horn, D M, additional, Keane, E F, additional, Kramer, M, additional, Künkel, L, additional, Levin, L, additional, Men, Y P, additional, Padmanabh, P V, additional, Ridolfi, A, additional, and Krishnan, V Venkatraman, additional

Published
2024
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11. An overview of the mid-infrared spectro-interferometer MATISSE: science, concept, and current status

Author

Matter, A., Lopez, B., Antonelli, P., Lehmitz, M., Bettonvil, F., Beckmann, U., Lagarde, S., Jaffe, W., Petrov, R. G., Berio, P., Millour, F., Robbe-Dubois, S., Glindemann, A., Bristow, P., Schoeller, M., Lanz, T., Henning, T., Weigelt, G., Heininger, M., Morel, S., Cruzalebes, P., Meisenheimer, K., Hofferbert, R., Wolf, S., Bresson, Y., Agocs, T., Allouche, F., Augereau, J. -C., Avila, G., Bailet, C., Behrend, J., Van Belle, G., Berger, J. -P., van Boekel, R., Bourget, P., Brast, R., Clausse, J. -M., Connot, C., Conzelmann, R., Csepany, G., Danchi, W. C., Delbo, M., Dominik, C., van Duin, A., Elswijk, E., Fantei, Y., Finger, G., Gabasch, A., Gonté, F., Graser, U., Guitton, F., Guniat, S., De Haan, M., Haguenauer, P., Hanenburg, H., Hofmann, K. -H., Hogerheijde, M., ter Horst, R., Hron, J., Hummel, C., Isderda, J., Ives, D., Jakob, G., Jasko, A., Jolley, P., Kiraly, S., Kragt, J., Kroener, T., Kroes, G., Kuindersma, S., Labadie, L., Laun, W., Leinert, C., Lizon, J. -L., Lucuix, C., Marcotto, A., Martinache, F., Martinot-Lagarde, G., Mauclert, N., Mehrgan, L., Meilland, A., Mellein, M., Menardi, S., Merand, A., Neumann, U., Nussbaum, E., Ottogalli, S., Palsa, R., Panduro, J., Pantin, E., Percheron, I., Duc, T. Phan, Pott, J. -U., Pozna, E., Roelfsema, R., Rupprecht, G., Schertl, D., Schmidt, C., Schuil, M., Spang, A., stegmeier, J., Tromp, N., Vakili, F., Vannier, M., Wagner, K., Venema, L., and Woillez, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

MATISSE is the second-generation mid-infrared spectrograph and imager for the Very Large Telescope Interferometer (VLTI) at Paranal. This new interferometric instrument will allow significant advances by opening new avenues in various fundamental research fields: studying the planet-forming region of disks around young stellar objects, understanding the surface structures and mass loss phenomena affecting evolved stars, and probing the environments of black holes in active galactic nuclei. As a first breakthrough, MATISSE will enlarge the spectral domain of current optical interferometers by offering the L and M bands in addition to the N band. This will open a wide wavelength domain, ranging from 2.8 to 13 um, exploring angular scales as small as 3 mas (L band) / 10 mas (N band). As a second breakthrough, MATISSE will allow mid-infrared imaging - closure-phase aperture-synthesis imaging - with up to four Unit Telescopes (UT) or Auxiliary Telescopes (AT) of the VLTI. Moreover, MATISSE will offer a spectral resolution range from R ~ 30 to R ~ 5000. Here, we present one of the main science objectives, the study of protoplanetary disks, that has driven the instrument design and motivated several VLTI upgrades (GRA4MAT and NAOMI). We introduce the physical concept of MATISSE including a description of the signal on the detectors and an evaluation of the expected performances. We also discuss the current status of the MATISSE instrument, which is entering its testing phase, and the foreseen schedule for the next two years that will lead to the first light at Paranal., Comment: SPIE Astronomical Telescopes and Instrumentation conference, June 2016, 11 pages, 6 Figures

Published
2016
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12. The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT – I. Discovery of seven new pulsars and two Pulsar Wind Nebula associations.

Author

Carli, E, Levin, L, Stappers, B W, Barr, E D, Breton, R P, Buchner, S, Burgay, M, Geyer, M, Kramer, M, Padmanabh, P V, Possenti, A, Venkatraman Krishnan, V, Becker, W, Filipović, M D, Maitra, C, Behrend, J, Champion, D J, Chen, W, Men, Y P, and Ridolfi, A

Subjects
SMALL magellanic cloud, PULSAR detection, PULSARS, LARGE magellanic cloud, MEERKAT, SOLAR radio bursts
Abstract

The sensitivity of the MeerKAT radio interferometer is an opportunity to probe deeper into the population of rare and faint extragalactic pulsars. The TRAPUM (TRAnsients and PUlsars with MeerKAT) collaboration has conducted a radio-domain search for accelerated pulsars and transients in the Small Magellanic Cloud (SMC). This partially targeted survey, performed at L band (856–1712 MHz) with the core array of the MeerKAT telescope in 2-h integrations, is twice as sensitive as the latest SMC radio pulsar survey. We report the discovery of seven new SMC pulsars, doubling this galaxy's radio pulsar population and increasing the total extragalactic population by nearly a quarter. We also carried out a search for accelerated millisecond pulsars in the SMC globular cluster NGC 121 using the full array of MeerKAT. This improved the previous upper limit on pulsed radio emission from this cluster by a factor of 6. Our discoveries reveal the first radio pulsar-PWN systems in the SMC, with only one such system previously known outside our Galaxy (the 'Crab pulsar twin' in the Large Magellanic Cloud, PSR J0540−6919). We associate the 59 ms pulsar discovery PSR J0040−7337, now the fastest spinning radio pulsar in the SMC, with the bow-shock Pulsar Wind Nebula (PWN) of supernova remnant DEM S5. We also present a new young pulsar with a 79 ms period, PSR J0048−7317, in a PWN recently discovered in a MeerKAT radio continuum image. Using the multibeam capability of MeerKAT, we localized our pulsar discoveries, and two previous Murriyang discoveries, to a positional uncertainty of a few arcseconds. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Direct constraint on the distance of y2 Velorum from AMBER/VLTI observations

Author

Millour, F., Petrov, R. G., Chesneau, O., Bonneau, D., Dessart, L., Bechet, C., Tallon-Bosc, I., Tallon, M., Thiébaut, E., Vakili, F., Malbet, F., Mourard, D., Zins, G., Roussel, A., Robbe-Dubois, S., Puget, P., Perraut, K., Lisi, F., Coarer, E. Le, Lagarde, S., Kern, P., Glück, L., Duvert, G., Chelli, A., Bresson, Y., Beckmann, U., Antonelli, P., Weigelt, G., Ventura, N., Vannier, M., Valtier, J. -C., Testi, L., Tatulli, E., Tasso, D., Stefanini, P., Stee, P., Solscheid, W., Schertl, D., Salinari, P., Sacchettini, M., Richichi, A., Reynaud, F., Rebattu, S., Rabbia, Y., Preibisch, T., Perrier, C., Pacini, F., Ohnaka, K., Nussbaum, E., Mouillet, D., Monin, J. -L., Mège, P., Mathias, P., Martinot-Lagarde, G., Mars, G., Marconi, A., Magnard, Y., Lopez, B., Contel, D. Le, Contel, J. -M. Le, Kraus, S., Kamm, D., Hofmann, K. -H., Utrera, O. Hernandez, Heininger, M., Heiden, M., Gil, C., Giani, E., Glentzlin, A., Gennari, S., Gallardo, A., Fraix-Burnet, D., Foy, R., Fossat, E., Forveille, T., Ferruzzi, D., Feautrier, P., Dugué, M., Driebe, T., De Souza, A. Domiciano, Delboulbé, A., Connot, C., Colin, J., Clausse, J. -M., Cassaing, F., Busoni, S., Bonhomme, S., Blöcker, T., Behrend, J., Baffa, C., Aristidi, E., Arezki, B., Agabi, K., Acke, B., Accardo, M., Kiekebusch, M., Rantakyrö, F., and Schoeller, Markus

Subjects
Astrophysics
Abstract

In this work, we present the first AMBER observations, of the Wolf-Rayet and O (WR+O) star binary system y2 Velorum. The AMBER instrument was used with the telescopes UT2, UT3, and UT4 on baselines ranging from 46m to 85m. It delivered spectrally dispersed visibilities, as well as differential and closure phases, with a resolution R = 1500 in the spectral band 1.95-2.17 micron. We interpret these data in the context of a binary system with unresolved components, neglecting in a first approximation the wind-wind collision zone flux contribution. We show that the AMBER observables result primarily from the contribution of the individual components of the WR+O binary system. We discuss several interpretations of the residuals, and speculate on the detection of an additional continuum component, originating from the free-free emission associated with the wind-wind collision zone (WWCZ), and contributing at most to the observed K-band flux at the 5% level. The expected absolute separation and position angle at the time of observations were 5.1±0.9mas and 66±15° respectively. However, we infer a separation of 3.62+0.11-0.30 mas and a position angle of 73+9-11°. Our analysis thus implies that the binary system lies at a distance of 368+38-13 pc, in agreement with recent spectrophotometric estimates, but significantly larger than the Hipparcos value of 258+41-31 pc.

Published
2006
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14. First AMBER/VLTI observations of hot massive stars

Author

Petrov, R. G., Millour, F., Chesneau, O., Weigelt, G., Bonneau, D., Stee, Ph., Kraus, S., Mourard, D., Meilland, A., Malbet, F., Lisi, F., Kern, P., Beckmann, U., Lagarde, S., Gennari, S., Lecoarer, E., Driebe, Th., Accardo, M., Robbe-Dubois, S., Ohnaka, K., Busoni, S., Roussel, A., Zins, G., Behrend, J., Ferruzi, D., Bresson, Y., Duvert, G., Nussbaum, E., Marconi, A., Feautrier, Ph., Dugué, M., Chelli, A., Tatulli, E., Heininger, M., Delboulbé, A., Bonhomme, S., Schertl, D., Testi, L., Mathias, Ph., Monin, J. -L., Gluck, L., Hofmann, K. H., Salinari, P., Puget, P., Clausse, J. -M., Fraix-Burnet, D., Foy, R., and Isella, A.

Subjects
Astrophysics
Abstract

AMBER is the first near infrared focal instrument of the VLTI. It combines three telescopes and produces spectrally resolved interferometric measures. This paper discusses some preliminary results of the first scientific observations of AMBER with three Unit Telescopes at medium (1500) and high (12000) spectral resolution. We derive a first set of constraints on the structure of the circumstellar material around the Wolf Rayet Gamma2 Velorum and the LBV Eta Carinae.

Published
2005
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16. A burst storm from the repeating FRB 20200120E in an M81 globular cluster

Author

Nimmo, K, primary, Hessels, J W T, additional, Snelders, M P, additional, Karuppusamy, R, additional, Hewitt, D M, additional, Kirsten, F, additional, Marcote, B, additional, Bach, U, additional, Bansod, A, additional, Barr, E D, additional, Behrend, J, additional, Bezrukovs, V, additional, Buttaccio, S, additional, Feiler, R, additional, Gawroński, M P, additional, Lindqvist, M, additional, Orbidans, A, additional, Puchalska, W, additional, Wang, N, additional, Winchen, T, additional, Wolak, P, additional, Wu, J, additional, and Yuan, J, additional

Published
2023
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17. The TRAPUM L-band survey for pulsars in Fermi-LAT gamma-ray sources

Author

Clark, C J, primary, Breton, R P, additional, Barr, E D, additional, Burgay, M, additional, Thongmeearkom, T, additional, Nieder, L, additional, Buchner, S, additional, Stappers, B, additional, Kramer, M, additional, Becker, W, additional, Mayer, M, additional, Phosrisom, A, additional, Ashok, A, additional, Bezuidenhout, M C, additional, Calore, F, additional, Cognard, I, additional, Freire, P C C, additional, Geyer, M, additional, Grießmeier, J-M, additional, Karuppusamy, R, additional, Levin, L, additional, Padmanabh, P V, additional, Possenti, A, additional, Ransom, S, additional, Serylak, M, additional, Venkatraman Krishnan, V, additional, Vleeschower, L, additional, Behrend, J, additional, Champion, D J, additional, Chen, W, additional, Horn, D, additional, Keane, E F, additional, Künkel, L, additional, Men, Y, additional, Ridolfi, A, additional, Dhillon, V S, additional, Marsh, T R, additional, and Papa, M A, additional

Published
2023
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18. TRAPUM upper limits on pulsed radio emission for SMC X-ray pulsar J0058−7218

Author

Carli, E, primary, Levin, L, additional, Stappers, B W, additional, Barr, E D, additional, Breton, R P, additional, Buchner, S, additional, Burgay, M, additional, Kramer, M, additional, Padmanabh, P V, additional, Possenti, A, additional, Venkatraman Krishnan, V, additional, Behrend, J, additional, Champion, D J, additional, Chen, W, additional, and Men, Y P, additional

Published
2022
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19. MATISSE

Author

Lopez, B., Lagarde, S., Wolf, S., Jaffe, W., Weigelt, G., Antonelli, P., Abraham, P., Augereau, J.-Ch., Beckman, U., Behrend, J., Berruyer, N., Bresson, Y., Chesneau, O., Clausse, J. M., Connot, C., Danchi, W. C., Delbo, M., Demyk, K., Domiciano, A., Dugué, M., Glazenborg, A., Graser, U., Hanenburg, H., Henning, Th., Heininger, M., Hofmann, K.-H., Hugues, Y., Jankov, S., Kraus, S., Laun, W., Leinert, Ch., Linz, H., Matter, A., Mathias, Ph., Meisenheimer, K., Menut, J.-L., Millour, F., Mosoni, L., Neumann, U., Niedzielski, A., Nussbaum, E., Petrov, R., Ratzka, Th., Robbe-Dubois, S., Roussel, A., Schertl, D., Schmider, F.-X., Stecklum, B., Thiebaut, E., Vakili, F., Wagner, K., Waters, L. B. F. M., Absil, O., Hron, J., Nardetto, N., Olofsson, J., Valat, B., Vannier, M., Goldman, B., Hönig, S., Cotton, W. D., Burton, W. B., editor, Christensen, Lars Lindberg, editor, and Moorwood, Alan, editor

Published
2009
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20. APerture Synthesis in the MID-Infrared with the VLTI

Author

Lopez, B., Wolf, S., Duguée, M., Graser, U., Mathias, Ph., Antonelli, P., Augereau, J.-C., Behrend, J., Berruyer, N., Bresson, Y., Chesneau, O., Connot, C., Demyk, K., DiFolco, E., Dutrey, A., Flament, S., Gitton, Ph., Glazenborg, A., Glindemann, A., Heininger, M., Henning, Th., Hofmann, K.-H., Hugues, Y., Jaffe, W., Jankov, S., Kraus, S., Lagarde, S., Leinert, Ch., Linz, H., Meisenheimer, K., Mosoni, L., Menut, J.-L., Neumann, U., Niedzielski, A., Przygodda, F., Puech, F., Ratzka, T., Rohloff, R., Roussel, A., Schertl, D., Schmider, F.-X., Stecklum, B., Thiéebaut, E., Vakili, F., Wagner, K., Weigelt, G., Leibundgut, Bruno, editor, Richichi, A., editor, Delplancke, F., editor, Paresce, F., editor, and Chelli, A., editor

Published
2008
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21. First AMBER/VLTI Observations of Hot Massive Stars

Author

Petrov, R. G., Millour, F., Chesneau, O., Weigelt, G., Bonneau, D., Stee, Ph., Kraus, S., Mourard, D., Meilland, A., Vannier, M., Malbet, F., Lisi, F., Antonelli, P., Kern, P., Beckmann, U., Lagarde, S., Perraut, K., Gennari, S., Coarer, E. Le, Driebe, Th., Accardo, M., Robbe-Dubois, S., Ohnaka, K., Busoni, S., Roussel, A., Zins, G., Behrend, J., Ferruzi, D., Bresson, Y., Duvert, G., Nussbaum, E., Marconi, A., Feautrier, Ph., Dugué, M., Chelli, A., Tatulli, E., Heininger, M., Delboulbe, A., Bonhomme, S., Schertl, D., Testi, L., Mathias, Ph., Monin, J. -L., Gluck, L., Hofmann, K. H., Salinari, P., Puget, P., Clausse, J. M., Fraix-Burnet, D., Foy, R., Isella, A., Leibundgut, Bruno, editor, Richichi, A., editor, Delplancke, F., editor, Paresce, F., editor, and Chelli, A., editor

Published
2008
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22. Four pulsar discoveries in NGC 6624 by TRAPUM using MeerKAT

Author

Abbate, F, primary, Ridolfi, A, additional, Barr, E D, additional, Buchner, S, additional, Burgay, M, additional, Champion, D J, additional, Chen, W, additional, Freire, P C C, additional, Gautam, T, additional, Grießmeier, J M, additional, Künkel, L, additional, Kramer, M, additional, Padmanabh, P V, additional, Possenti, A, additional, Ransom, S, additional, Serylak, M, additional, Stappers, B W, additional, Venkatraman Krishnan, V, additional, Behrend, J, additional, Breton, R P, additional, Levin, L, additional, and Men, Y, additional

Published
2022
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25. Wafer fused p-InP/p-GaAs heterojunctions

Author

Salomonsson, F., Streubel, K., Bentell, J., Hammar, M., Keiper, D., Westphalen, R., Piprek, J., Sagalowicz, L., Rudra, A., and Behrend, J.

Subjects
Integrated circuits -- Wafer-scale integration, Semiconductor doping -- Research, Semiconductor wafers -- Research, Semiconductors -- Junctions, Physics
Abstract

The design and characterization of low resistive wafer-fused heterojunctions between p-InP and p-GaAs were investigated. Doping profiles across the interface and interface contamination with carbon or oxygen were characterized using secondary ion mass spectroscopy. Results showed that the wafer-fused heterojunctions had high crystalline quality. Moreover, the large lattice mismatch between InP and GaAs was accommodated by edge dislocations.

Published
1998

27. Ectopic expression of murine CD47 minimizes macrophage rejection of human hepatocyte xenografts in immunodeficient mice

Author

Johan M. Waern, Karsten Wursthorn, Nicholas D. Huntington, Kai Schulze, Qinggong Yuan, Behrend J. Zacher, M Bock, Michael P. Manns, Carlos A. Guzmán, Urda Rüdrich, Helene Strick-Marchand, James P. DiSanto, Michael Ott, Pablo D. Becker, Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany, Twincore, Centre for Experimental and Clinical Infection Research, Hannover, Germany, and Medical and Oncology Clinic, Södra Älvsborgs Sjukhus, Borås, Sweden.

Subjects
Graft Rejection, Transplantation, Heterologous, CD47 Antigen, Biology, Sensitivity and Specificity, Immunocompromised Host, Mice, Random Allocation, Transduction (genetics), In vivo, Animals, Humans, Receptors, Immunologic, Cells, Cultured, Cell Proliferation, Immunodeficient Mouse, Mice, Inbred BALB C, Hepatology, Macrophages, CD47, Laboratory mouse, Hep G2 Cells, Antigens, Differentiation, Molecular biology, In vitro, Transplantation, Gene Expression Regulation, Models, Animal, Hepatocytes, Cancer research, Ectopic expression
Abstract

Macrophages play an important role in the rejection of xenogeneic cells and therefore represent a major obstacle to generating chimeric mice with human xenografts that are useful tools for basic and preclinical medical research. The signal inhibitory regulatory protein α (SIRPα) receptor is a negative regulator of macrophage phagocytic activity and interacts in a species-specific fashion with its ligand CD47. Furthermore, SIRPα polymorphism in laboratory mouse strains significantly affects the extent of human CD47-mediated toleration of human xenotransplants. Aiming to minimize macrophage activity and thus optimize human cell engraftment in immunodeficient mice, we lentivirally transduced murine CD47 (Cd47) into human liver cells. Human HepG2 liver cells expressing Cd47 were less frequently contacted and phagocytosed by murine RAW264.7 macrophages in vitro than their Cd47-negative counterparts. For the generation of human-mouse chimeric livers in immunodeficient BALB-ΔRAG/γ(c) -uPA (urokinase-type plasminogen activator) mice, freshly thawed cryopreserved human hepatocytes were transduced with a lentiviral expression vector for Cd47 using a refined in vitro transduction protocol immediately before transplantation. In vivo, Cd47-positive human primary hepatocytes were selectively retained following engraftment in immunodeficient mice, leading to at least a doubling of liver repopulation efficiencies. Conclusion: We conclude that ectopic expression of murine Cd47 in human hepatocytes selectively favors engraftment upon transplantation into mice, a finding that should have a profound impact on the generation of robust humanized small animal models. Moreover, dominance of ectopically expressed murine Cd47 over endogenous human CD47 should also widen the spectrum of immunodeficient mouse strains suitable for humanization. (HEPATOLOGY 2012).

Published
2012

28. Rapid early HDV RNA decline in the peripheral blood but prolonged intrahepatic hepatitis delta antigen persistence after liver transplantation

Author

C.-Thomas Bock, Cihan Yurdaydin, Michael P. Manns, Berna Savaş, Jens Rosenau, Karsten Wursthorn, Fabian A. Helfritz, Florian Puls, Heiner Wedemeyer, Behrend J. Zacher, Hans L. Tillmann, Christian P. Strassburg, Frank Lehner, Ingmar Mederacke, Juergen Klempnauer, Ulrich Lehmann, Eva Herrmann, Natalie Filmann, Benjamin Heidrich, and Birgit Bremer

Subjects
Adult, Male, HBsAg, Time Factors, Hepatitis D, Chronic, viruses, Hepatitis C virus, medicine.disease_cause, Models, Biological, Young Adult, Liver disease, Humans, Medicine, Retrospective Studies, Hepatitis delta Antigens, Hepatitis B virus, Hepatitis B Surface Antigens, Hepatology, medicine.diagnostic_test, business.industry, virus diseases, cccDNA, Middle Aged, biochemical phenomena, metabolism, and nutrition, medicine.disease, Virology, Hepatitis D, Liver Transplantation, Virus Latency, Liver, Liver biopsy, Immunology, RNA, Viral, Female, Hepatitis D virus, Hepatitis Delta Virus, business
Abstract

Background & Aims Chronic HDV infection is an inflammatory liver disease and liver transplantation (LTX) remains the only curative treatment option for most patients. The hepatitis D virus (HDV) uses HBsAg as its surface protein, however, it is controversial to what extend HDV may be detected independently of HBsAg in blood and liver after LTX. The aims of this study were to investigate kinetics of HDV RNA and HBsAg early after LTX, to apply the data to a mathematical model and to study long-term persistence of HDV after LTX. Methods We retrospectively analyzed 26 patients with chronic hepatitis delta who underwent LTX between 1994 and 2009. Blood samples were obtained every 1–3days during the first 14days after LTX. Data were applied to a mathematical model to study viral kinetics. Available liver biopsy samples were stained for HBV and HDV viral antigens and tested for HBV DNA/cccDNA. Results HBsAg and HDV RNA became negative after a median of 5days (range 1–13) and 4days (range 1–10), respectively. Early HDV RNA and HBsAg decline paralleled almost exactly in all patients; however the mathematical model showed a high variability of virion death. HDAg stained positive in transplanted livers in six patients in the absence of liver HBV DNA/cccDNA, serum-HBsAg, and HDV RNA for up to 19months after LTX. Conclusions HDV RNA and HBsAg decline follow almost identical kinetic patterns within the first days after LTX. Nevertheless, intrahepatic latency of HDAg has to be considered when exploring novel concepts to withdraw HBIG.

Published
2012

29. An overview of the mid-infrared spectro-interferometer MATISSE: science, concept, and current status

Author

Matter, A., additional, Lopez, B., additional, Antonelli, P., additional, Lehmitz, M., additional, Bettonvil, F., additional, Beckmann, U., additional, Lagarde, S., additional, Jaffe, W., additional, Petrov, R., additional, Berio, P., additional, Millour, F., additional, Robbe-Dubois, S., additional, Glindemann, A., additional, Bristow, P., additional, Schoeller, M., additional, Lanz, T., additional, Henning, T., additional, Weigelt, G., additional, Heininger, M., additional, Morel, S., additional, Cruzalebes, P., additional, Meisenheimer, K., additional, Hofferbert, R., additional, Wolf, S., additional, Bresson, Y., additional, Agocs, T., additional, Allouche, F., additional, Augereau, J.-C., additional, Avila, G., additional, Bailet, C., additional, Behrend, J., additional, van Belle, G., additional, Berger, J.-P., additional, van Boekel, R., additional, Bourget, P., additional, Brast, R., additional, Clausse, J.-M., additional, Connot, C., additional, Conzelmann, R., additional, Csepany, G., additional, Danchi, W. C., additional, Delbo, M., additional, Dominik, C., additional, van Duin, A., additional, Elswijk, E., additional, Fantei, Y., additional, Finger, G., additional, Gabasch, A., additional, Gonté, F., additional, Graser, U., additional, Guitton, F., additional, Guniat, S., additional, De Haan, M., additional, Haguenauer, P., additional, Hanenburg, H., additional, Hofmann, K.-H., additional, Hogerheijde, M., additional, ter Horst, R., additional, Hron, J., additional, Hummel, C, additional, Isderda, J., additional, Ives, D., additional, Jakob, G., additional, Jasko, A., additional, Jolley, P., additional, Kiraly, S., additional, Kragt, J., additional, Kroener, T., additional, Kroes, G., additional, Kuindersma, S., additional, Labadie, L., additional, Laun, W., additional, Leinert, C., additional, Lizon, J.-L., additional, Lucuix, C., additional, Marcotto, A., additional, Martinache, F., additional, Martinot-Lagarde, G., additional, Mauclert, N., additional, Mehrgan, L., additional, Meilland, A., additional, Mellein, M., additional, Menardi, S., additional, Merand, A., additional, Neumann, U., additional, Nussbaum, E., additional, Ottogalli, S., additional, Palsa, R., additional, Panduro, J., additional, Pantin, E., additional, Percheron, I., additional, Phan Duc, T., additional, Pott, J.-U., additional, Pozna, E., additional, Roelfsema, R., additional, Rupprecht, G., additional, Schertl, D., additional, Schmidt, C., additional, Schuil, M., additional, Spang, A., additional, Stegmeier, J., additional, Tromp, N., additional, Vakili, F., additional, Vannier, M., additional, Wagner, K., additional, Venema, L., additional, and Woillez, J., additional

Published
2016
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30. Increased HEV seroprevalence in patients with autoimmune hepatitis

Author

Karsten Wursthorn, Torsten Witte, Heike Bantel, Birgit Bremer, Reinhold E. Schmidt, Sven Pischke, Pothakamuri Venkata Suneetha, Richard Taubert, Kinan Rifai, R. Raupach, Michael P. Manns, Heiner Wedemeyer, A. Gisa, Behrend J. Zacher, Steffen B. Wiegand, and Jerome Schlue

Subjects
Male, viruses, T-Lymphocytes, lcsh:Medicine, Autoimmune hepatitis, medicine.disease_cause, Hepatitis, Arthritis, Rheumatoid, Hepatitis E virus, Seroepidemiologic Studies, Medicine, Gastrointestinal Infections, lcsh:Science, Hepatitis, Chronic, Aged, 80 and over, Multidisciplinary, Coinfection, T Cells, Liver Diseases, virus diseases, Hepatitis C, Hepatitis B, Middle Aged, Hepatitis E, Hepatitis, Autoimmune, RNA, Viral, Infectious diseases, Female, Autoimmune Hepatitis, Research Article, Adult, Adolescent, Clinical Research Design, Hepatitis C virus, Immune Cells, Gastroenterology and Hepatology, Viral diseases, Microbiology, Immunocompromised Host, Virology, Humans, Hepatitis Antibodies, Biology, Aged, Retrospective Studies, business.industry, lcsh:R, medicine.disease, digestive system diseases, Case-Control Studies, Co-Infections, Immunology, lcsh:Q, Clinical Immunology, business
Abstract

Background Hepatitis E virus (HEV) infection takes a clinically silent, self-limited course in the far majority of cases. Chronic hepatitis E has been reported in some cohorts of immunocompromised individuals. The role of HEV infections in patients with autoimmune hepatitis (AIH) is unknown. Methods 969 individuals were tested for anti-HEV antibodies (MP-diagnostics) including 208 patients with AIH, 537 healthy controls, 114 patients with another autoimmune disease, rheumatoid arthritis (RA), and 109 patients with chronic HCV- or HBV-infection (HBV/HCV). Patients with AIH, RA and HBV/HCV were tested for HEV RNA. HEV-specific proliferative T cell responses were investigated using CFSE staining and in vitro stimulation of PBMC with overlapping HEV peptides. Results HEV-antibodies tested more frequently positive in patients with AIH (n = 16; 7.7%) than in healthy controls (n = 11; 2.0%; p = 0.0002), patients with RA (n = 4; 3.5%; p = 0.13) or patients with HBV/HCV infection (n = 2; 2.8%; p = 0.03). HEV-specific T cell responses could be detected in all anti-HEV-positive AIH patients. One AIH patient receiving immunosuppression with cyclosporin and prednisolone and elevated ALT levels had acute hepatitis E but HEV viremia resolved after reducing immunosuppressive medication. None of the RA or HBV/HCV patients tested HEV RNA positive. Conclusions Patients with autoimmune hepatitis but not RA or HBV/HCV patients are more likely to test anti-HEV positive. HEV infection should been ruled out before the diagnosis of AIH is made. Testing for HEV RNA is also recommended in AIH patients not responding to immunosuppressive therapy.

Published
2013

31. Early on treatment detection of nucelos(t)ide analogue resistant minor variants of Hepatitis B virus (HBV) with ultra deep-pyrosequencing (UDPS) in chronic hepatitis B(CHB) patients

Author

Katja Deterding, M.P. Manns, H. Wedemeyer, S.B. Wiegand, G Steinert, M. Cornberg, Behrend J. Zacher, A Taranta, and Karsten Wursthorn

Subjects
Genetics, HBsAg, Gastroenterology, virus diseases, Lamivudine, Single-nucleotide polymorphism, Amplicon, Biology, Resistance mutation, Virology, Viral Breakthrough, Genotype, Adefovir, medicine, medicine.drug
Abstract

Introduction: UDPS allows the detection of minor viral variants during the natural course and antiviral treatment in HBV-infected patients. It could be shown that double infections with two HBV genotypes and minor strains carrying resistance mutations not detected by clonal sequencing could be analyzed. Here we tested a method for analyzing multiple HBV genotypes in a single sample as well as its potential to identify resistance mutations in patients months before viral breakthrough. Patients and methods: A custom HBV sample was constructed by equimolar pooling of PCR amplicons derived from viral nucleic acid extracts from the serum of three different CHB patients. They had been identified as HBV genotypes B and D. Two samples were described as genotype D (one as wild-type, one as carrier of the resistance mutation rtM204V), and one sample as genotype B (wild-type). The genotype D wild-type developed lamivudine (LMV) and adefovir (ADV) resistance later on treatment. UDPS was performed on a GS Flx 454 sequencer (Roche). Sequencing data was analyzed using GenomiX Workbench (CLC Bio). Results: Sequence analysis showed 37,07% of reads mapping to HBV genotype B (subtype adw), 61.99% to genotype D (subtypes w3 and ayw3) while the remaining 0,96% where scattered among other genotypes. Single nucleotide polymorphism (SNP) analysis of the sequences mapped to distinct genotypes clearly discriminated between wild-type and mutated HBV strains. For one patient, previously described as infected with wild-type HBV genotype D, a minor variant (coverage 35, frequency 100%) in the viral quasi species showed mutations at position rtM204 and rtI233, mediating viral resistance to LMV and ADV. Follow-up of this patient revealed a viral breakthrough with a major species resistant to LMV and ADV (rtM204V, rtI233V) 14 months later. Conclusions: UDPS is a feasible method for the identification of HBV viral sequences including genotype and resistance mutations. The detection of minor variants carrying resistance-bearing mutations more than a year prior to viral breakthrough could constitute a new tool for individualizing antiviral treatment, especially with low genetic barrier nucleos(t)ide analogues. Whether the occurrence of minor quasi-species with resistance mutations could also be reflected by serological parameters like serum HBsAg is currently investigated.

Published
2013

32. MF59-Adjuvanted seasonal influenza vaccine including H1N1 leads to robust serological response rates in immunocompromised patients after liver and kidney transplantation

Author

A Müller-Heine, Karsten Wursthorn, J Buchta, T Ganten, C. Blume, C Schröder, Armin Koch, A Großhennig, M.P. Manns, Christian P. Strassburg, S. Pischke, and Behrend J. Zacher

Subjects
Transplantation, Seasonal influenza, business.industry, Liver and kidney, Immunology, Gastroenterology, MF59, Medicine, business, Serology
Published
2012

33. HBeAg-positive hepatitis delta: virological patterns and clinical long-term outcome

Author

Fatih Oğuz Önder, Ramazan Idilman, R. Raupach, Michael P. Manns, Behrend J. Zacher, Beatriz Calle Serrano, Hans L. Tillmann, Heiner Wedemeyer, Benjamin Heidrich, A.M. Bozdayi, Kalliopi Zachou, Gökhan Kabaçam, Birgit Bremer, Katja Deterding, Cihan Yurdaydin, Hakan Bozkaya, and Andrzej Taranta

Subjects
Adult, Male, HBsAg, medicine.medical_specialty, Hepatitis B virus, Adolescent, Hepatitis D, Chronic, viruses, medicine.disease_cause, Gastroenterology, Liver disease, Young Adult, Internal medicine, Germany, medicine, Humans, Hepatitis B e Antigens, Child, Aged, Aged, 80 and over, Hepatitis B Surface Antigens, Hepatology, business.industry, virus diseases, Hepatitis B, Middle Aged, medicine.disease, Prognosis, Hepatitis D, digestive system diseases, HBeAg, Hepatocellular carcinoma, Child, Preschool, Immunology, DNA, Viral, Disease Progression, Female, Hepatitis D virus, Hepatitis Delta Virus, business
Abstract

Background and Aims The presence of the hepatitis B virus (HBV)-eAg in patients with hepatitis B is associated with higher HBV replication and with an increased risk to develop liver-related clinical endpoints defined as liver related death, liver transplantation, development of hepatocellular carcinoma and hepatic decompensation. The aim of this study was to investigate the role of HBeAg in patients co-infected with the hepatitis D virus (HDV). Methods We studied virological markers of HBV and HDV infection and as well as biochemical and clinical features of liver disease in a cohort of 534 anti-HDV-positive patients. In addition, we compared the clinical long-term outcome of HBeAg-positive HDV-infected patients with HBeAg-negative control patients matched for age, gender and baseline-MELD score. Results HBeAg-positive hepatitis delta was detected in 71 of 534 patients (13.3%). HBeAg positivity was associated with a higher biochemical disease activity and higher HBsAg levels in HDV co-infected patients. Sixty one per cent of the HBeAg-positive HDV-infected patients presented with HBV DNA levels below 2000 IU/ml, at least once during follow-up. Both HBeAg-positive and -negative patients showed a similar severe clinical long-term course with about half of the patients developing a liver-related clinical complication after a median follow-up period of 51 months (range: 9–193 months). Conclusions HBV DNA levels are low in both HBeAg-negative and HBeAg-positive patients suggesting suppressive effects of HDV on HBV irrespective of the phase of HBV infection. The clinical long-term outcome of HBeAg-positive patients is not different to HBeAg-negative patients infected with the HDV.

Published
2011

34. Development of a protocol for the quantitative determination of HBeAg using the Elecsys® HBeAg immunoassay

Author

Michael Manns, Jerzy Jaroszewicz, Behrend J. Zacher, Karsten Wursthorn, M. Darnedde, and H. Wedemeyer

Subjects
medicine.medical_specialty, Paul ehrlich institute, Gastroenterology, Hepatitis B, Chronic, Virology, Internal medicine, medicine, Humans, In patient, Hepatitis B e Antigens, Reference standards, Hepatitis, Immunoassay, Hepatology, medicine.diagnostic_test, business.industry, virus diseases, Hepatitis B, Reference Standards, medicine.disease, digestive system diseases, Quantitative determination, Infectious Diseases, HBeAg, Immunology, business, Algorithms
Abstract

Summary. Loss of hepatitis ‘e’ antigen (HBeAg) in patients with HBeAg-positive chronic hepatitis B is associated with improved long-term clinical outcome and is defined as a goal of antiviral treatment by clinical practice guidelines. Recent studies suggest that baseline levels and on-treatment monitoring of HBeAg levels may identify patients most likely to respond to therapy. The aim of this study was the development of a protocol for the quantitative determination of HBeAg using the Elecsys® HBeAg immunoassay. The linear range of the Elecsys® HBeAg immunoassay was established using recombinant HBeAg and five different diluents. The assay was validated against the Paul Ehrlich Institute (PEI) international standard serum. Linearity was demonstrated up to a cut-off index (COI) of 1000, independent of the diluent used. Optimal linearity was obtained using the Elecsys® Universal Diluent. Using the PEI reference standard, conversion factors were established as 4.50 COI for 1 PEIU/mL corresponding to 0.222 PEIU/mL for a COI of 1. Based on the results from these analyses, a simple algorithm for the quantitative measurement of HBeAg using the Elecsys® HBeAg immunoassay was developed. Using a simple algorithm with an initial 1:40 dilution, the Elecsys® HBeAg assay provides robust quantification of serum HBeAg in an easy-to-use and rapid system. The use of a commercially available, standardized diluent improves comparability between laboratories.

Published
2011

35. Onkologie in der Hausarztpraxis: Ist-Analyse und Bedarfserhebung aus der Sicht praktizierender Hausärzte

Author

Dahlhaus, A, Güthlin, C, Behrend, J, Herrler, C, Gerlach, FM, and Siebenhofer, A

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Hintergrund: Hausärzte sind für die meisten Patienten mit einer Krebserkrankung beständiger Ansprechpartner und Koordinator während des gesamten Krankheitsverlaufs und verfügen damit häufig als Einzige über alle relevanten Informationen. Bisher fehlt eine systematische[for full text, please go to the a.m. URL], 45. Kongress für Allgemeinmedizin und Familienmedizin, Forum Medizin 21

Published
2011
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36. Correlation between the Elecsys HBsAg II assay and the Architect assay for the quantification of hepatitis B surface antigen (HBsAg) in the serum

Author

Karsten Wursthorn, Markus Cornberg, Heiner Wedemeyer, Michael P. Manns, Behrend J. Zacher, Martina Darnedde, Jerzy Jaroszewicz, Ingmar Mederacke, and R. Raupach

Subjects
HBsAg, Hepatitis B virus, Genotype, Pyrimidinones, medicine.disease_cause, Hepatitis b surface antigen, Therapeutic goal, Hepatitis B, Chronic, Orthohepadnavirus, Virology, Telbivudine, Drug Resistance, Viral, Medicine, Humans, Hepatitis B e Antigens, Longitudinal Studies, Immunoassay, Hepatitis B Surface Antigens, biology, business.industry, Clinical Laboratory Techniques, virus diseases, Nucleosides, Hepatitis B, biology.organism_classification, medicine.disease, digestive system diseases, Infectious Diseases, Hepadnaviridae, Lamivudine, Immunology, Mutation, Reagent Kits, Diagnostic, business, medicine.drug, Thymidine
Abstract

Hepatitis B surface antigen (HBsAg) clearance during chronic hepatitis B (CHB) infection is associated with improved long-term clinical outcome, so is considered an important therapeutic goal in CHB. Studies have shown that serum HBsAg quantification during, and at end of, treatment may predict long-term HBsAg loss.Performance comparison of the qualitative Elecsys HBsAg II assay using a quantitative research protocol and an established quantitative HBsAg assay.A dilution algorithm was developed for the Elecsys HBsAg II assay to allow quantification of HBsAg levels; this was used to measure HBsAg levels in a range of samples including sera from patients infected with different HBV genotypes, HBV mutants, and longitudinal samples from patients undergoing antiviral treatment. Results were compared with those from the quantitative Architect HBsAg assay.There was significant overall correlation between Elecsys and Architect assays (correlation coefficient [r]=0.97; p0.001). HBsAg levels measured with both assays correlated well in all phases of infection (r=0.80-0.96), across all genotypes tested (HBV genotype A, r=0.89; HBV genotype D, r=0.97), and in samples with lamivudine-resistant mutations (r=0.94). Bland-Altman analysis showed only minor discordance between assays in different phases of chronic HBV-infection (3.8-5.1%). This strong correlation was also present for sera with lower HBsAg concentrations. On-treatment HBsAg levels were similar when measured with either assay.Using a simple dilution algorithm, the quantitative Elecsys HBsAg II assay reliably determined serum HBsAg levels in a wide range of samples, and showed very high correlation with the Architect HBsAg assay.

Published
2010

37. Solutions to IBM POWER8 verification challenges

Author

Schubert, K.-D., primary, Ludden, J. M., additional, Ayub, S., additional, Behrend, J., additional, Brock, B., additional, Copty, F., additional, German, S. M., additional, Hershkovitz, O., additional, Horbach, H., additional, Jackson, J. R., additional, Keuerleber, K., additional, Koesters, J., additional, Leitner, L. S., additional, Meil, G. B., additional, Meissner, C., additional, Morad, R., additional, Nahir, A., additional, Paruthi, V., additional, Peterson, R. D., additional, Pratt, R. R., additional, Rimon, M., additional, and Schumann, J. A., additional

Published
2015
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39. MATISSE, perspective of imaging in the mid-infrared at the VLTI

Author

Lopez, B., Antonelli, P., Wolf, S., Lagarde, S., Jaffe, W., Navarro, R., Graser, U., Petrov, R., Weigelt, G., Bresson, Y., Hofmann, K. H., Beckman, U., Henning, T., Laun, W., Ch. Leinert, Robbe-Dubois, S., Vakili, F., Richichi, A., Abraham, P., C Augereau, J., Behrend, J., Ph. Berio, Berruyer, N., Chesneau, O., Clausse, J. M., Connot, C., Demyk, K., Danchi, W. C., Dugué, M., Finger, G., Flament, S., Glazenborg, A., Hannenburg, H., Heininger, M., Hugues, Y., Hron, J., Jankov, S., Kerschbaum, F., Kroes, G., Linz, H., L Lizon, J., Ph. Mathias, Mathar, R., Matter, A., Menut, J. L., Meisenheimer, K., Millour, F., Nardetto, N., Neumann, U., Nussbaum, E., Niedzielski, A., Mosoni, L., Olofsson, J., Rabbia, Y., Ratzka, T., Rigal, F., Roussel, A., Schertl, D., François-Xavier Schmider, Stecklum, B., Éric Thiébaut, Vannier, M., Valat, B., Wagner, K., Waters, L. B. F. M., Laboratoire Hippolyte Fizeau (FIZEAU), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire Universitaire d'Astrophysique de Nice (LUAN), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), Observatoire de la Côte d'Azur (OCA), Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Astrophysik [Wien], Universität Wien, Thüringer Landessternwarte Tautenburg (TLS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

International audience; MATISSE is foreseen as a mid-infrared spectro-interferometer combining the beams of up to four UTs/ATs of the Very Large Telescope Interferometer (VLTI) of the European Southern Observatory. The related science case study demonstrates the enormous capability of a new generation mid-infrared beam combiner. MATISSE will constitute an evolution of the two-beam interferometric instrument MIDI. MIDI is a very successful instrument which offers a perfect combination of spectral and angular resolution. New characteristics present in MATISSE will give access to the mapping and the distribution of the material (typically dust) in the circumstellar environments by using a wide mid-infrared band coverage extended to L, M and N spectral bands. The four beam combination of MATISSE provides an efficient UV-coverage : 6 visibility points are measured in one set and 4 closure phase relations which can provide aperture synthesis images in the mid-infrared spectral regime.

Published
2008

40. Recent Progress in the VLBI2010 Development

Author

Behrend, J., Boehm, J., Charlot, P., Clark, T., Corey, B., Gipson, J., Haas, R., Koyama, Y., MacMillan, D., Malkin, Z., Niell, A., Nilsson, T., Petrachenko, B., Rogers, A., Tuccari, G., Wresnik, J., Max-Planck-Institut für Radioastronomie (MPIFR), NVI, Inc., NASA Goddard Space Flight Center (GSFC), institut de geodesie et geophysique de Vienne (INSTITUT DE GEODESIE ET GEOPHYSIQUE), Institut de geodesie et geophysique, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), MIT Haystack Observatory, Massachusetts Institute of Technology (MIT), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], Kashima Space Technology Center, National Institute of Information and Communications Technology [Tokyo, Japan] (NICT), Pulkovo Observatory, Geodetic Survey Division, Istituto di Radioastronomia di Noto, and Istituto Nazionale di Astrofisica (INAF)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], next generation VLBI2010, IVS, geodetic VLBI, Monte Carlo simulations
Abstract

chapter in book series "International Association of Geodesy Symposia" book "Observing our Changing Earth" ISBN 978-3-540-85425-8; International audience; From October 2003 to September 2005, the International VLBI Service for Geodesy and Astrometry (IVS) examined current and future requirements for geodetic VLBI, including all components from antennas to analysis. IVS Working Group 3 ‘VLBI 2010', which was tasked with this effort, concluded with recommendations for a new generation of VLBI systems. These recommendations were based on the goals of achieving 1 mm measurement accuracy on global baselines, performing continuous measurements for time series of station positions and Earth orientation parameters, and reaching a turnaround time from measurement to initial geodetic results of less than 24 hours. To realize these recommendations and goals, along with the need for low cost of construction and operation, requires a complete examination of all aspects of geodetic VLBI including equipment, processes, and observational strategies. Hence, in October 2005, the IVS VLBI2010 Committee (V2C) commenced work on defining the VLBI2010 system specifications. In this paper we give a summary of the recent progress of the VLBI2010 project.

Published
2008

41. An asymmetry detected in the disk of Kappa CMa with the AMBER/VLTI

Author

Meilland, Anthony, Millour, Florentin, Stee, Philippe, Domiciano De Souza, Armando, Petrov, Romain, Mourard, Denis, Jankov, Slobodan, Robbe-Dubois, Sylvie, Spang, Alain, Arisitidi, Eric, Antonelli, P., Beckmann, U., Bresson, Y., Chelli, A., Dugué, M., Duvert, G., Glück, L., Kern, P., Lagarde, S., Le Coarer, E., Lisi, F., Malbet, F., Perraut, K., Puget, P., Robbe-Dubois, S., Weigelt, G., Zins, G., Accardo, M., Acke, B., Agabi, K., Arezki, B., Altariba, E., Baffa, C., Behrend, J., Blöcker, T., Bonhomme, S., Busoni, S., Cassaing, F., Clausse, J.-M., Connot, C., Delboulbé, A., Domicinano De Souza, A., Driebe, T., Feautrier, P., Ferruzzi, D., Forveille, T., Fossat, E., Foy, R., Fraix-Burnet, D., Gallardo, A., Gennari, S., Glentzlin, A., Giani, E., Gilinst, C., Heiden, M., Heininger, M., Hernandez, O., Hofmann, K.-H., Kamm, D., Kraus, S., Le Contel, D., Le Contel, J.-M., Lopez, B., Magnard, Y., Marconi, A., Mars, G., Martinot-Lagarde, G., Mathias, P., Millour, F., Monin, J.-L., Mouillet, D., Mourard, D., Mège, P., Nussbaum, E., Ohnaka, K., Pacini, F., Perrier, C., Rabbia, Y., Rebattu, S., Reynaud, F., Richichi, A., Roussel, A., Sacchettini, M., Salinari, P., Schertl, D., Solscheid, W., Stee, P., Stefanini, P., Tallon, M., Tallon-Bosc, I., Tasso, D., Tatulli, E., Testi, L., Valtier, J.-C., Vannier, M., Ventura, N., Kiekebusch, M., Schöller, M., Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Universitaire d'Astrophysique de Nice (LUAN), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars: emission-line, Astrophysics (astro-ph), Stars: individual (kappa CMa), FOS: Physical sciences, Be, Astrophysics, Techniques: high angular resolution, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars: Keplerian rotation, Techniques: interferometric, Stars: circumstellar matter, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

International audience; Aims. We study the geometry and kinematics of the circumstellar environment of the Be star Kappa CMa in the Br gamma emission line and its nearby continuum. Methods. We use the VLTI/AMBER instrument operating in the K band which provides a spatial resolution of about 6 mas with a spectral resolution of 1500 to study the kinematics within the disk and to infer its rotation law. In order to obtain more kinematical constraints we also use an high spectral resolution Pa beta line profile obtain in December 2005 at the Observatorio do Pico do Dios, Brazil and we compile V/R line profile variations and spectral energy distribution data points from the literature. Results. Using differential visibilities and differential phases across the Br gamma line we detect an asymmetry in the disk. Moreover, we found that kappa CMa seems difficult to fit within the classical scenario for Be stars, illustrated recently by alpha Arae observations, i.e. a fast rotating B star close to its breakup velocity surrounded by a Keplerian circumstellar disk with an enhanced polar wind. Finally we discuss the possibility for kappa CMa to be a critical rotator with a Keplerian rotating disk and try to see if the detected asymmetry can be interpreted within the "one-armed" viscous disk framework.

Published
2006

42. MATISSE a four beams combiner in the mid-infrared for the VLTI

Author

Lagarde, S., Lopez, B., Antonelli, P., Beckman, U., Behrend, J., Bresson, Y., Chesneau, O., Connot, C., Dugué, M., Glazenborg, A., Graser, U., Henning, T., Hofmann, K.H., Heininger, M., Hugues, Y., Jaffe, W., Kraus, S., Laun, W., Leinert, Ch., Matter, A., Menut, J.L., Millour, F., Neumann, U., Nussbaum, E., Niedzielski, A., Mosoni, L., Petrov., G., Ratzka, R., Robbe-Dubois, S., Roussel, A., Wagner, K., Waters, L.B.F.M., Weigelt, G., Wolf, S., Laboratoire Hippolyte Fizeau (FIZEAU), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)

Abstract

Advances in Stellar Interferometry, SPIE 6268, (2006); International audience

Published
2006

43. MATISSE, perspective of imaging in the mid-infrared at the VLTI

Author

Lopez, B., Wolf, S., Lagarde, S., Abraham, P., Antonelli, P., Augereau, J.C., Beckman, U., Behrend, J., Berruyer, N., Bresson, Y., Chesneau, O., Clausse, J.M., Connot, C., Demyk, K., Danchi, W.C., Dugué, M., Flament, S., Glazenborg, A., Graser, U., Henning, T., Hofmann, K.H., Heininger, M., Hugues, Y., Jaffe, W., Jankov, S., Kraus, S., Laun, W., Leinert, C., Linz, H., Mathias, P., Meisenheimer, K., Matter, A., Menut, J.L., Millour, F., Neumann, U., Nussbaum, E., Niedzielski, A., Mosonic, L., Petrov, R.G., Ratzka, T., Robbe-Dubois, S., Roussel, A., Schertl, D., Schmider, F.-X., Stecklum, B., Thiebaut, E., Vakili, F., Wagner, K., Waters, L.B.F.M., Weigelt, G., Monnier, J.D., Schöller, M., Laboratoire Hippolyte Fizeau (FIZEAU), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Low Energy Astrophysics (API, FNWI), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, and Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, 0103 physical sciences, 010303 astronomy & astrophysics, 01 natural sciences, 0105 earth and related environmental sciences
Abstract

Our objective is the development of mid-infrared imaging at the VLTI. The related science case study demonstrates the enormous capability of a new generation mid-infrared beam combiner. MATISSE will constitute an evolution of the two-beam interferometric instrument MIDI by increasing the number of recombined beams up to four. MIDI is a very successful instrument which offers a perfect combination of spectral and angular resolution. New characteristics present in MATISSE will give access to the mapping and the distribution of the material (typically dust) in the circumstellar environments by using a wide mid-infrared band coverage extended to L, M, N and Q spectral bands. The four beam combination of MATISSE provides an efficient UV-coverage: 6 visibility points are measured in one set and 4 closure phase relations which can provide for the first time aperture synthesis images in the mid-infrared spectral regime. The mid-infrared spectral domain is very relevant for the study of the environment of various astrophysical sources. Our science case studies show the wide field of applications of MATISSE. They will be illustrated in the first part of this presentation through the perspective of imaging the circumstellar environments/discs of young stellar objects. The MATISSE characteristics will be given in a second part of the presentation.

Published
2006

46. First AMBER/VLTI Observations of Hot Massive Stars

Author

Romain Petrov, Millour, F., Chesneau, O., Weigelt, G., Bonneau, D., Ph. Stee, Kraus, S., Mourard, D., Meilland, A., Vannier, M., Malbet, F., Lisi, F., Antonelli, P., Kern, P., Beckmann, U., Lagarde, S., Perraut, K., Gennari, S., Le Coarer, E., Th. Driebe, Accardo, M., Robbe-Dubois, S., Ohnaka, K., Busoni, S., Roussel, A., Zins, G., Behrend, J., Ferruzi, D., Bresson, Y., Duvert, G., Nussbaum, E., Marconi, A., Ph. Feautrier, Dugué, M., Chelli, A., Tatulli, E., Heininger, M., Delboulbe, A., Bonhomme, S., Schertl, D., Testi, L., Ph. Mathias, L Monin, J., Gluck, L., Hofmann, K. H., Salinari, P., Puget, P., Clausse, J. M., Didier Fraix-Burnet, D., Renaud Foy, Isella, A., Laboratoire Universitaire d'Astrophysique de Nice (LUAN), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), European Southern Observatory (ESO), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Centre de Recherche Astrophysique de Lyon (CRAL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

8 pages; International audience; AMBER is the first near infrared focal instrument of the VLTI. It combines three telescopes and produces spectrally resolved interferometric measures. This paper discusses some preliminary results of the first scientific observations of AMBER with three Unit Telescopes at medium (1500) and high (12000) spectral resolution. We derive a first set of constraints on the structure of the circumstellar material around the Wolf Rayet gamma2 Velorum and the LBV eta Carinae.

Published
2005

47. Disk and wind interaction in the young stellar object MWC 297 spatially resolved with VLTI/AMBER

Author

Malbet, F., Benisty, M., de Wit, W.J., Kraus, S., Meilland, A., Millour, F., Tatulli, E., Berger, J.P., Chesneau, O., Hofmann, K.H., Isella, A., Natta, A., Petrov, R., Preibisch, T., Stee, P., Testi, L., Weigelt, G., Antonelli, P., Beckmann, U., Bresson, Y., Chelli, A., Duvert, G., Glück, L., Kern, P., Lagarde, S., Le Coarer, E., Lisi, F., Perraut, K., Robbe-Dubois, S., Roussel, A., Zins, G., Accardo, M., Acke, B., Agabi, K., Arezki, B., Aristidi, E., Baffa, C., Behrend, J., Blöcker, T., Bonhomme, S., Busoni, S., Cassaing, F., Clausse, J.-M., Colin, J., Connot, C., Delboulbé, A., Driebe, T., Dugué, M., Feautrier, P., Ferruzzi, D., Forveille, T., Fossat, E., Foy, Renaud, Fraix-Burnet, D., Gallardo, A., Gennari, S., Glentzlin, A., Giani, E., Gil, C., Heiden, M., Heininger, M., Kamm, D., Le Contel, D., Le Contel, J.-M., Lopez, B., Magnard, Y., Marconi, A., Mars, G., Martinot-Lagarde, G., Mathias, P., Monin, J.-L., Mouillet, D., Mourard, D., Mège, P., Nussbaum, E., Ohnaka, K., Pacheco, J., Pacini, F., Perrier, C., Puget, P., Rabbia, Y., Rebattu, S., Reynaud, François, Richichi, A., Sacchettini, M., Salinari, P., Schertl, D., Solscheid, W., Stefanini, P., Tallon, Michel, Tallon-Bosc, Isabelle, Tasso, D., Valtier, J.-C., Vannier, M., Ventura, N., Kiekebusch, M., Rantakyrö, F., Schöller, M., Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Universitaire d'Astrophysique de Nice (LUAN), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), ONERA - The French Aerospace Lab [Châtillon], ONERA, Centre de Recherche Astrophysique de Lyon (CRAL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), PHOTONIQUE, XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), AMBER, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ONERA-Université Paris Saclay (COmUE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Protoplanetary disks, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Pre-main-sequence stars, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Planetary systems, Early-type stars, Emission-line stars, Accretion disks, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Infrared, Interferometric Techniques, Astrophysics::Galaxy Astrophysics
Abstract

The young stellar object MWC 297 has been observed with the VLT interferometer equipped with the AMBER instrument. MWC 297 has been spatially resolved in the continuum with a visibility of 0.50 as well as in the Br gamma emission line where the visibility decrease to a lower value of 0.33. This change in the visibility with the wavelength can be interpreted by the presence of an optically thick disk responsible for the visibility in the continuum and of a stellar wind traced by Br gamma and whose apparent size is 40% larger. We validate this interpretation by building a model of the stellar environment that combines a geometrically thin, optically thick accretion disk model consisting of gas and dust, and a latitude-dependent stellar wind outflowing above the disk surface. The continuum emission and visibilities obtained from this model are fully consistent with the interferometric AMBER data. They agree also with existing optical, near-infrared spectra and other broad-band near-infrared interferometric visibilities. A picture emerges in which MWC 297 is surrounded by an equatorial flat disk that is possibly still accreting and an outflowing wind which has a much higher velocity in the polar region than at the equator. [abridged], Comment: 13 pages; to be published in A&A; Acceptance day: 11/10/2005

Published
2005
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48. MATISSE

Author

Lopez, B., primary, Lagarde, S., additional, Wolf, S., additional, Jaffe, W., additional, Weigelt, G., additional, Antonelli, P., additional, Abraham, P., additional, Augereau, J.-Ch., additional, Beckman, U., additional, Behrend, J., additional, Berruyer, N., additional, Bresson, Y., additional, Chesneau, O., additional, Clausse, J. M., additional, Connot, C., additional, Danchi, W. C., additional, Delbo, M., additional, Demyk, K., additional, Domiciano, A., additional, Dugué, M., additional, Glazenborg, A., additional, Graser, U., additional, Hanenburg, H., additional, Henning, Th., additional, Heininger, M., additional, Hofmann, K.-H., additional, Hugues, Y., additional, Jankov, S., additional, Kraus, S., additional, Laun, W., additional, Leinert, Ch., additional, Linz, H., additional, Matter, A., additional, Mathias, Ph., additional, Meisenheimer, K., additional, Menut, J.-L., additional, Millour, F., additional, Mosoni, L., additional, Neumann, U., additional, Niedzielski, A., additional, Nussbaum, E., additional, Petrov, R., additional, Ratzka, Th., additional, Robbe-Dubois, S., additional, Roussel, A., additional, Schertl, D., additional, Schmider, F.-X., additional, Stecklum, B., additional, Thiebaut, E., additional, Vakili, F., additional, Wagner, K., additional, Waters, L. B. F. M., additional, Absil, O., additional, Hron, J., additional, Nardetto, N., additional, Olofsson, J., additional, Valat, B., additional, Vannier, M., additional, Goldman, B., additional, Hönig, S., additional, and Cotton, W. D., additional

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49. APerture Synthesis in the MID-Infrared with the VLTI

Author

Lopez, B., primary, Wolf, S., additional, Duguée, M., additional, Graser, U., additional, Mathias, Ph., additional, Antonelli, P., additional, Augereau, J.-C., additional, Behrend, J., additional, Berruyer, N., additional, Bresson, Y., additional, Chesneau, O., additional, Connot, C., additional, Demyk, K., additional, DiFolco, E., additional, Dutrey, A., additional, Flament, S., additional, Gitton, Ph., additional, Glazenborg, A., additional, Glindemann, A., additional, Heininger, M., additional, Henning, Th., additional, Hofmann, K.-H., additional, Hugues, Y., additional, Jaffe, W., additional, Jankov, S., additional, Kraus, S., additional, Lagarde, S., additional, Leinert, Ch., additional, Linz, H., additional, Meisenheimer, K., additional, Mosoni, L., additional, Menut, J.-L., additional, Neumann, U., additional, Niedzielski, A., additional, Przygodda, F., additional, Puech, F., additional, Ratzka, T., additional, Rohloff, R., additional, Roussel, A., additional, Schertl, D., additional, Schmider, F.-X., additional, Stecklum, B., additional, Thiéebaut, E., additional, Vakili, F., additional, Wagner, K., additional, and Weigelt, G., additional

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50. First AMBER/VLTI Observations of Hot Massive Stars

Author

Petrov, R. G., primary, Millour, F., additional, Chesneau, O., additional, Weigelt, G., additional, Bonneau, D., additional, Stee, Ph., additional, Kraus, S., additional, Mourard, D., additional, Meilland, A., additional, Vannier, M., additional, Malbet, F., additional, Lisi, F., additional, Antonelli, P., additional, Kern, P., additional, Beckmann, U., additional, Lagarde, S., additional, Perraut, K., additional, Gennari, S., additional, Coarer, E. Le, additional, Driebe, Th., additional, Accardo, M., additional, Robbe-Dubois, S., additional, Ohnaka, K., additional, Busoni, S., additional, Roussel, A., additional, Zins, G., additional, Behrend, J., additional, Ferruzi, D., additional, Bresson, Y., additional, Duvert, G., additional, Nussbaum, E., additional, Marconi, A., additional, Feautrier, Ph., additional, Dugué, M., additional, Chelli, A., additional, Tatulli, E., additional, Heininger, M., additional, Delboulbe, A., additional, Bonhomme, S., additional, Schertl, D., additional, Testi, L., additional, Mathias, Ph., additional, Monin, J. -L., additional, Gluck, L., additional, Hofmann, K. H., additional, Salinari, P., additional, Puget, P., additional, Clausse, J. M., additional, Fraix-Burnet, D., additional, Foy, R., additional, and Isella, A., additional

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