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224 results on '"Kastner, J. H."'

53. The magnetosphere of the close accreting PMS binary V4046 Sgr AB

Author

Gregory, S. G., Holzwarth, V. R., Donati, J.-F, Hussain, G. A. J., Montmerle, T., Alecian, E., Alencar, S. H. P., Argiroffi, C., Audard, M., Bouvier, J., Damiani, F., Güdel, M., Huenemoerder, D. P., Kastner, J. H., Maggio, A., Sacco, G. G., Wade, G. A., Gregory, S. G., Holzwarth, V. R., Donati, J.-F, Hussain, G. A. J., Montmerle, T., Alecian, E., Alencar, S. H. P., Argiroffi, C., Audard, M., Bouvier, J., Damiani, F., Güdel, M., Huenemoerder, D. P., Kastner, J. H., Maggio, A., Sacco, G. G., and Wade, G. A.

Abstract

We present a preliminary 3D potential field extrapolation model of the joint magnetosphere of the close accreting PMS binary V4046 Sgr. The model is derived from magnetic maps obtained as part of a coordinated optical and X-ray observing program

Published
2017

55. The Herschel Planetary Nebula Survey (HerPlaNS). I. Data overview and analysis demonstration with NGC 6781

Author

Ladjal, D., Exter, K. M., Szczerba, R., Siodmiak, N., Aleman, I., van, Hoof P. A. M., Kastner, J. H., Montez, Jr. R., McDonald, I., Wittkowski, M., Sandin, C., Ramstedt, S., DeMarco, O., Villaver, E., Chu, Y.-H., Vlemmings, W., Sahai, R., Lopez, J. A., Balick, B., Zijlstra, A., Tielens, A. G. G. M., Rattray, R. E., Behar, E., Blackman, E. G., Hebden, K., Hora, J. L., Murakawa, K., Nordhaus, J., Nordon, R., Ueta, Toshiya, Otsuka, M., Izumiura, Hideyuki, and Yamamura, Issei

Subjects
Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Spatial distribution, 01 natural sciences, Spectral line, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, planetary nebulae: general, Spectroscopy, 010303 astronomy & astrophysics, infrared: stars, Astrophysics::Galaxy Astrophysics, Physics, Nebula, 010308 nuclear & particles physics, White dwarf, Astronomy and Astrophysics, Mass ratio, Planetary nebula, Astrophysics - Astrophysics of Galaxies, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), stars: winds, Halo, Astrophysics::Earth and Planetary Astrophysics
Abstract

著者人数: 33名, Accepted: 2014-03-14, 資料番号: SA1140080000

Published
2014

57. Herschel Planetary Nebula Survey (HerPlaNS) First detection of OH+ in planetary nebulae

Author

Aleman, I., 植田, 稔也, Ladjal, D., Exter, K. M., Kastner, J. H., Montez Jr., R., Tielens, A. G. G. M., Chu, Y.-H., 泉浦, 秀行, McDonald, I., Sahai, R., Siodmiak, N., Szczerba, R., van Hoof, P. A. M., Villaver, E., Vlemmings, W., Wittkowski, M., Zijlstra, A. A., Ueta, Toshiya, Izumiura, Hideyuki, Aleman, I., 植田, 稔也, Ladjal, D., Exter, K. M., Kastner, J. H., Montez Jr., R., Tielens, A. G. G. M., Chu, Y.-H., 泉浦, 秀行, McDonald, I., Sahai, R., Siodmiak, N., Szczerba, R., van Hoof, P. A. M., Villaver, E., Vlemmings, W., Wittkowski, M., Zijlstra, A. A., Ueta, Toshiya, and Izumiura, Hideyuki

Abstract

著者人数: 18名, Accepted: 2014-04-07

Published
2015

60. THE CHANDRA PLANETARY NEBULA SURVEY (ChanPlaNS). III. X-RAY EMISSION FROM THE CENTRAL STARS OF PLANETARY NEBULAE

Author

Montez Jr., R., primary, Kastner, J. H., additional, Balick, B., additional, Behar, E., additional, Blackman, E., additional, Bujarrabal, V., additional, Chu, Y.-H., additional, Corradi, R. L. M., additional, De Marco, O., additional, Frank, A., additional, Freeman, M., additional, Frew, D. J., additional, Guerrero, M. A., additional, Jones, D., additional, Lopez, J. A., additional, Miszalski, B., additional, Nordhaus, J., additional, Parker, Q. A., additional, Sahai, R., additional, Sandin, C., additional, Schonberner, D., additional, Soker, N., additional, Sokoloski, J. L., additional, Steffen, M., additional, Toalá, J. A., additional, Ueta, T., additional, Villaver, E., additional, and Zijlstra, A., additional

Published
2015
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61. THECHANDRAPLANETARY NEBULA SURVEY (CHANPLANS). II. X-RAY EMISSION FROM COMPACT PLANETARY NEBULAE

Author

Freeman, M., primary, Montez, R., additional, Kastner, J. H., additional, Balick, B., additional, Frew, D. J., additional, Jones, D., additional, Miszalski, B., additional, Sahai, R., additional, Blackman, E., additional, Chu, Y.-H., additional, De Marco, O., additional, Frank, A., additional, Guerrero, M. A., additional, Lopez, J. A., additional, Zijlstra, A., additional, Bujarrabal, V., additional, Corradi, R. L. M., additional, Nordhaus, J., additional, Parker, Q. A., additional, Sandin, C., additional, Schönberner, D., additional, Soker, N., additional, Sokoloski, J. L., additional, Steffen, M., additional, Toalá, J. A., additional, Ueta, T., additional, and Villaver, E., additional

Published
2014
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63. HerschelPlanetary Nebula Survey (HerPlaNS)

Author

Aleman, I., primary, Ueta, T., additional, Ladjal, D., additional, Exter, K. M., additional, Kastner, J. H., additional, Montez, R., additional, Tielens, A. G. G. M., additional, Chu, Y.-H., additional, Izumiura, H., additional, McDonald, I., additional, Sahai, R., additional, Siódmiak, N., additional, Szczerba, R., additional, van Hoof, P. A. M., additional, Villaver, E., additional, Vlemmings, W., additional, Wittkowski, M., additional, and Zijlstra, A. A., additional

Published
2014
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64. TheHerschelPlanetary Nebula Survey (HerPlaNS)

Author

Ueta, T., primary, Ladjal, D., additional, Exter, K. M., additional, Otsuka, M., additional, Szczerba, R., additional, Siódmiak, N., additional, Aleman, I., additional, van Hoof, P. A. M., additional, Kastner, J. H., additional, Montez, R., additional, McDonald, I., additional, Wittkowski, M., additional, Sandin, C., additional, Ramstedt, S., additional, De Marco, O., additional, Villaver, E., additional, Chu, Y.-H., additional, Vlemmings, W., additional, Izumiura, H., additional, Sahai, R., additional, Lopez, J. A., additional, Balick, B., additional, Zijlstra, A., additional, Tielens, A. G. G. M., additional, Rattray, R. E., additional, Behar, E., additional, Blackman, E. G., additional, Hebden, K., additional, Hora, J. L., additional, Murakawa, K., additional, Nordhaus, J., additional, Nordon, R., additional, and Yamamura, I., additional

Published
2014
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66. Gas and Dust Associated with the Strange, Isolated Star BP Piscium

Author

Zuckerman, B, Melis, C, Song, Inseok, Meier, David, Perrin, Marshall, D., Macintosh, B A, Marois, Christian, Weinberger, Alycia J., Rhee, Joseph H., Graham, J, Kastner, J. H., Bessell, Michael, Zuckerman, B, Melis, C, Song, Inseok, Meier, David, Perrin, Marshall, D., Macintosh, B A, Marois, Christian, Weinberger, Alycia J., Rhee, Joseph H., Graham, J, Kastner, J. H., and Bessell, Michael

Abstract

We have carried out a multiwavelength observational campaign demonstrating some of the remarkable properties of the infrared-bright variable star BP Psc. Surrounded by a compact dusty, gaseous disk, this little-studied late G (or early K) type star emits

Published
2008

68. The magnetosphere of the close accreting PMS binary V4046 Sgr AB

Author

Gregory, S. G., primary, Holzwarth, V. R., additional, Donati, J.-F., additional, Hussain, G. A. J., additional, Montmerle, T., additional, Alecian, E., additional, Alencar, S. H. P., additional, Argiroffi, C., additional, Audard, M., additional, Bouvier, J., additional, Damiani, F., additional, Güdel, M., additional, Huenemoerder, D. P., additional, Kastner, J. H., additional, Maggio, A., additional, Sacco, G. G., additional, and Wade, G. A., additional

Published
2013
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69. Evidence for variable, correlated X-ray and optical/IR extinction towards the nearby, pre-main-sequence binary TWA 30.

Author

Principe, David A., Sacco, G., Kastner, J. H., Stelzer, B., and Alcalá, J. M.

Subjects
BINARY systems (Astronomy), ASTRONOMICAL observations, STELLAR luminosity function, INTERSTELLAR medium, DISKS (Astrophysics)
Abstract

We present contemporaneous XMM-Newton X-ray and ground-based optical/near-IR spectroscopic observations of the nearby (D ≈ 42 pc), low-mass (mid-M) binary system TWA 30A and 30B. The components of this wide (separation ~3400 au) binary are notable for their nearly edge-on disc viewing geometries, high levels of variability, and evidence for collimated stellar outflows. We obtained XMM-Newton X-ray observations of TWA 30A and 30B in 2011 June and July, accompanied (respectively) by Infrared Telescope Facility SpeX (near-IR) and VLT XSHOOTER (visible/near-IR) spectroscopy obtained within ~20 h of the X-ray observations. TWA 30A was detected in both XMM-Newton observations at relatively faint intrinsic X-ray luminosities (LX ~ 8 x 1027 erg s-1) compared to stars of similar mass and age. The intrinsic (0.15-2.0 keV) X-ray luminosities measured in 2011 had decreased by a factor 20-100 relative to a 1990 (ROSAT) X-ray detection. TWA 30B was not detected, and we infer an upper limit on its X-ray Luminosity of LX ≲ 3.0 x 1027 erg s-1. We measured a decrease in visual extinction towards TWA 30A (from AV ≈ 14.9 to AV ≈ 4.7) between the two 2011 observing epochs, and we find evidence for a corresponding significant decrease in X-ray absorbing column (NH). The apparent correlated change in AV and NH is suggestive of variable obscuration of the stellar photosphere by disc material composed of both gas and dust. However, in both observations, the inferred NH to AV ratio is lower than that typical of the interstellar medium, suggesting that the disc is either depleted of gas or is deficient in metals in the gas phase. [ABSTRACT FROM AUTHOR]

Published
2016
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70. THECHANDRAX-RAY SURVEY OF PLANETARY NEBULAE (CHANPLANS): PROBING BINARITY, MAGNETIC FIELDS, AND WIND COLLISIONS

Author

Kastner, J. H., primary, Montez, R., additional, Balick, B., additional, Frew, D. J., additional, Miszalski, B., additional, Sahai, R., additional, Blackman, E., additional, Chu, Y.-H., additional, De Marco, O., additional, Frank, A., additional, Guerrero, M. A., additional, Lopez, J. A., additional, Rapson, V., additional, Zijlstra, A., additional, Behar, E., additional, Bujarrabal, V., additional, Corradi, R. L. M., additional, Nordhaus, J., additional, Parker, Q. A., additional, Sandin, C., additional, Schönberner, D., additional, Soker, N., additional, Sokoloski, J. L., additional, Steffen, M., additional, Ueta, T., additional, and Villaver, E., additional

Published
2012
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72. THE CLOSE T TAURI BINARY SYSTEM V4046 Sgr: ROTATIONALLY MODULATED X-RAY EMISSION FROM ACCRETION SHOCKS

Author

Argiroffi, C., primary, Maggio, A., additional, Montmerle, T., additional, Huenemoerder, D. P., additional, Alecian, E., additional, Audard, M., additional, Bouvier, J., additional, Damiani, F., additional, Donati, J.-F., additional, Gregory, S. G., additional, Güdel, M., additional, Hussain, G. A. J., additional, Kastner, J. H., additional, and Sacco, G. G., additional

Published
2012
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74. An X-Ray Outburst from the Rapidly Accreting Young Star that Illuminates McNeil's Nebula

Author

NAVAL OBSERVATORY FLAGSTAFF AZ, Kastner, J. H., Richmond, M., Grosso, N., Weintraub, D. A., Simon, T., NAVAL OBSERVATORY FLAGSTAFF AZ, Kastner, J. H., Richmond, M., Grosso, N., Weintraub, D. A., and Simon, T.

Abstract

Young, low-mass stars are luminous X-ray sources whose powerful X-ray flares may exert a profound influence over the process of planet formation. The origin of the X-ray emission is uncertain. Although many (or perhaps most) recently formed, low-mass stars emit X-rays as a consequence of solar-like coronal activity, it also has been suggested that X-ray emission may be a direct result of mass accretion onto the forming star. The authors report on X-ray imaging spectroscopy observations that reveal a factor ^50 increase in the X-ray flux from a young star that is at present undergoing a spectacular optical/infrared outburst (this star illuminates McNeil's nebula). The outburst seems to be due to the sudden onset of a phase of rapid accretion. The coincidence of a surge in X-ray brightness with the optical/infrared eruption demonstrates that strongly enhanced high-energy emission from young stars can occur as a consequence of high accretion rates. The authors suggest that such accretion-enhanced X-ray emission from erupting young stars may be short-lived, because intense star disk magnetospheric interactions are quenched rapidly by the subsequent flood of new material onto the star. (1 table, 3 figures, 30 refs.), Published in Nature, v430 p429-431, 22 Jul 2004. Prepared in collaboration with the Rochester Institute of Technology, Rochester, NY; Laboratoire d' Astrophysique de Grenoble, Universite Joseph-Fourier, Grenoble, France; Vanderbilt University, Nashville, TN; Institute for Astronomy, Honolulu, HI; University of Rochester, Rochester, NY; and Goddard Space Flight Center, Greenbelt, MD.

Published
2004

75. GSC 07396-00759 = V4046 Sgr C[D]: A WIDE-SEPARATION COMPANION TO THE CLOSE T TAURI BINARY SYSTEM V4046 Sgr AB

Author

Kastner, J. H., primary, Sacco, G. G., additional, Montez, R., additional, Huenemoerder, D. P., additional, Shi, H., additional, Alecian, E., additional, Argiroffi, C., additional, Audard, M., additional, Bouvier, J., additional, Damiani, F., additional, Donati, J.-F., additional, Gregory, S. G., additional, Güdel, M., additional, Hussain, G. A. J., additional, Maggio, A., additional, and Montmerle, T., additional

Published
2011
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76. Early results from ChanPLaNS: Mystery of hard X-ray emitting CSPNe

Author

Montez, Rodolfo, primary, Kastner, J. H., additional, Balick, B., additional, Behar, E., additional, Blackman, E., additional, Bujarrabal, V., additional, Chu, Y.-H., additional, Corradi, R., additional, De Marco, O., additional, Frank, A., additional, Frew, D., additional, Guerrero, M., additional, Kwok, S., additional, Lopez, J. A., additional, Miszalski, B., additional, Nordhaus, J., additional, Parker, Q., additional, Sahai, R., additional, Sandin, C., additional, Schoenberner, D., additional, Soker, N., additional, Sokoloski, J., additional, Steffen, W., additional, Ueta, T., additional, Villaver, E., additional, and Zijlstra, A., additional

Published
2011
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78. A MULTI-WAVELENGTH SPECTRAL AND POLARIMETRIC STUDY OF THE JET OF 3C 264

Author

Perlman, E. S., primary, Padgett, C. A., additional, Georganopoulos, M., additional, Worrall, D. M., additional, Kastner, J. H., additional, Franz, G., additional, Birkinshaw, M., additional, Dulwich, F., additional, O'Dea, C. P., additional, Baum, S. A., additional, Sparks, W. B., additional, Biretta, J. A., additional, Lara, L., additional, Jester, S., additional, and Martel, A., additional

Published
2009
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90. X-rays from HH 210in the Orion nebula

Author

Grosso, N., Feigelson, E. D., Getman, K. V., Kastner, J. H., Bally, J., McCaughrean, M. J., Grosso, N., Feigelson, E. D., Getman, K. V., Kastner, J. H., Bally, J., and McCaughrean, M. J.

Abstract

We report the detection during the Chandra Orion Ultradeep Project(COUP) of two soft, constant, and faint X-ray sources associated with the Herbig-Haro object HH 210. HH 210is located at the tip of the NNE finger of the emission line system bursting out of the BN-KL complex, northwest of the Trapezium cluster in the OMC-1 molecular cloud. Using a recent Hαimage obtained with the ACSimager on board HST, and taking into account the known proper motions of HH 210emission knots, we show that the position of the brightest X-ray source, COUP 703, coincides with the emission knot 154-040a of HH 210, which is the emission knot of HH 210having the highest tangential velocity (425 km s-1). The second X-ray source, COUP 704, is located on the complicated emission tail of HH 210close to an emission line filament and has no obvious optical/infrared counterpart. Spectral fitting indicates for both sources a plasma temperature of ~0.8 MK and absorption-corrected X-ray luminosities of about 1030erg s-1(0.5–2.0 keV). These X-ray sources are well explained by a model invoking a fast-moving, radiative bow shock in a neutral medium with a density of ~12 000 cm-3. The X-ray detection of COUP 704therefore reveals, in the complicated HH 210region, an energetic shock not yet identified at other wavelengths.

Published
2006
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93. Herschel Planetary Nebula Survey (HerPlaNS) First detection of OH+ in planetary nebulae.

Author

Aleman, I., Ueta, T., Ladjal, D., Exter, K. M., Kastner, J. H., Montez Jr., R., Tielens, A. G. G. M., Chu, Y.-H., Izumiura, H., McDonald, I., Sahai, R., Siódmiak, N., Szczerba, R., van Hoof, P. A. M., Villaver, E., Vlemmings, W., Wittkowski, M., and Zijlstra, A. A.

Subjects
PLANETARY nebulae, FAR infrared lasers, PHOTODISSOCIATION, CIRCUMSTELLAR matter, ASTROCHEMISTRY
Abstract

Aims. We report the first detections of OH+ emission in planetary nebulae (PNe). Methods. As part of an imaging and spectroscopy survey of 11 PNe in the far-IR using the PACS and SPIRE instruments aboard the Herschel Space Observatory, we performed a line survey in these PNe over the entire spectral range between 51 μm and 672 μm to look for new detections. Results. The rotational emission lines of OH+ at 152.99, 290.20, 308.48, and 329.77 μm were detected in the spectra of three planetary nebulae: NGC 6445, NGC6720, and NGC 6781. Excitation temperatures and column densities derived from these lines are in the range of 27–47 K and 2 × 1010–4 × 1011 cm−2, respectively. Conclusions. In PNe, the OH+ rotational line emission appears to be produced in the photodissociation region (PDR) in these objects. The emission of OH+ is observed only in PNe with hot central stars (Teff > 100 000 K), suggesting that high-energy photons may play a role inOH+ formation and its line excitation in these objects, as seems to be the case for ultraluminous galaxies. [ABSTRACT FROM AUTHOR]

Published
2014
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94. The Herschel Planetary Nebula Survey (HerPlaNS) I. Data overview and analysis demonstration with NGC6781.

Author

Ueta, T., Ladjal, D., Exter, K. M., Otsuka, M., Szczerba, R., Siódmiak, N., Aleman, I., van Hoof, P. A. M., Kastner, J. H., Montez Jr., R., McDonald, I., Wittkowski, M., Sandin, C., Ramstedt, S., DeMarco, O., Villaver, E., Chu, Y.-H., Vlemmings, W., Izumiura, H., and Sahai, R.

Subjects
PLANETARY nebulae, ASTRONOMICAL surveys, DATA analysis, SPECTRAL energy distribution, INTERPLANETARY dust
Abstract

Context. This is the first of a series of investigations into far-IR characteristics of 11 planetary nebulae (PNe) under the Herschel Space Observatory open time 1 program, Herschel Planetary Nebula Survey (HerPlaNS). Aims. Using the HerPlaNS data set, we look into the PN energetics and variations of the physical conditions within the target nebulae. In the present work, we provide an overview of the survey, data acquisition and processing, and resulting data products. Methods. We performed (1) PACS/SPIRE broadband imaging to determine the spatial distribution of the cold dust component in the target PNe and (2) PACS/SPIRE spectral-energy-distribution and line spectroscopy to determine the spatial distribution of the gas component in the target PNe. Results. For the case of NGC 6781, the broadband maps confirm the nearly pole-on barrel structure of the amorphous carbon-rich dust shell and the surrounding halo having temperatures of 26−40K. The PACS/SPIRE multiposition spectra show spatial variations of far-IR lines that reflect the physical stratification of the nebula. We demonstrate that spatially resolved far-IR line diagnostics yield the (Te, ne) profiles, from which distributions of ionized, atomic, and molecular gases can be determined. Direct comparison of the dust and gas column mass maps constrained by the HerPlaNS data allows to construct an empirical gas-to-dust mass ratio map, which shows a range of ratios with the median of 195 ± 110. The present analysis yields estimates of the total mass of the shell to be 0.86 M⊙, consisting of 0.54 M⊙ of ionized gas, 0.12 M⊙ of atomic gas, 0.2 M⊙ of molecular gas, and 4 × 10−3 M⊙ of dust grains. These estimates also suggest that the central star of about 1.5M⊙ initial mass is terminating its PN evolution onto the white dwarf cooling track. Conclusions. The HerPlaNS data provide various diagnostics for both the dust and gas components in a spatially resolved manner. In the forthcoming papers of the HerPlaNS series we will explore the HerPlaNS data set fully for the entire sample of 11 PNe. [ABSTRACT FROM AUTHOR]

Published
2014
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95. Molecules in the transition disk orbiting T Chamaeleontis.

Author

Sacco, G. G., Kastner, J. H., Forveille, T., Principe, D., Montez Jr., R., Zuckerman, B., and Hily-Blant, P.

Subjects
*CIRCUMSTELLAR matter, *SPECTRUM analysis, *ORION Nebula, *EARLY stars, *INTERSTELLAR medium
Abstract

Aims. We seek to establish the presence and properties of gas in the circumstellar disk orbiting T Cha, a nearby (d ~ 110 pc), relatively evolved (age ~5-7 Myr) yet actively accreting 1.5 M☉ T Tauri star. Methods. We used the Atacama Pathfinder Experiment (APEX) 12 m radiotelescope to search for submillimeter molecular emission from the T Cha disk, and we reanalyzed archival XMM-Newton imaging spectroscopy of T Cha to ascertain the intervening absorption due to disk gas along the line of sight to the star (NH). Results. We detected submillimeter rotational transitions of 12CO, 13CO, HCN, CN, and HCO+ from the T Cha disk. The 12CO line (and possibly the 13CO line) appears to display a double-peaked line profile indicative of Keplerian rotation; hence, these molecular line observations constitute the first direct demonstration of the presence of cold molecular gas orbiting T Cha. Analysis of the CO emission line data indicates that the disk around T Cha has a mass (Mdisk,H2= 80 Mⴲ) similar to, but more compact (Rdisk,CO ~ 80 AU) than other nearby, evolved molecular disks (e.g., V4046 Sgr, TW Hya, MP Mus) in which cold molecular gas has been previously detected. The HCO+/13CO and HCN/13CO line ratios measured for T Cha appear similar to those of other evolved circumstellar disks (i.e., TW Hya and V4046 Sgr). The CN/13CO ratio appears somewhat weaker, but due to the low signal-to-noise ratio of our detection, this discrepancy is not strongly significant. Analysis of the XMM-Newton X-ray spectroscopic data shows that the atomic absorption NH toward T Cha is one to two orders of magnitude larger than toward the other nearby T Tauri with evolved disks, which are seen at much lower inclination angles. Furthermore, the ratio between atomic absorption and optical extinction NH/AV toward T Cha is higher than the typical value observed for the interstellar medium and young stellar objects in the Orion nebula cluster. This may suggest that the fraction of metals in the disk gas is higher than in the interstellar medium. However, an X-ray absorption model appropriate for the physical and chemical conditions of a circumstellar disk is required to address this issue. Conclusions. Our results confirm that pre-main-sequence stars older than ~5 Myr retain cold molecular disks when accreting, and that those relatively evolved disks display similar physical and chemical properties. [ABSTRACT FROM AUTHOR]

Published
2014
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