中文
相关论文

相关论文: Interstellar extinction and abundances of simple d…

200 篇论文

With the 30-m IRAM radio telescope, we observed several massive star forming regions at wavelengths of 3-4 and 2 mm. The temperature of the gas in the sources was estimated from the lines of CH$_{3}$CCH and from the transitions of the…

星系天体物理 · 物理学 2023-02-13 A. G. Pazukhin , I. I. Zinchenko , E. A. Trofimova , C. Henkel

We report interstellar C II column densities or upper limits determined from weak absorption of the 2325.4029 A intersystem transition observed in six translucent sightlines with STIS. The sightlines sample a wide range of interstellar…

天体物理学 · 物理学 2009-11-10 U. J. Sofia , J. T. Lauroesch , D. M. Meyer , S. I. B. Cartledge

We explore the relationship between dust-emission derived reddening \EBV\ and atomic hydrogen column density N(H I) derived from 21 cm emission surveys. We consider measurements at galactic latitude $|b| \ga 20$\degr\ and \EBV\ $\la$ 0.1…

星系天体物理 · 物理学 2015-06-17 H. S. Liszt

We are studying the column density distribution of all nearby giant molecular clouds. As part of this project we generated several all sky extinction maps. They are calculated using the median near infrared colour excess technique applied…

星系天体物理 · 物理学 2009-11-13 J. Rowles , D. Froebrich

Near ultraviolet observations of OH+ and OH in diffuse molecular clouds reveal a preference for different environments. The dominant absorption feature in OH+ arises from a main component seen in CH+ (that with the highest CH+/CH column…

星系天体物理 · 物理学 2015-06-18 A. J. Porras , S. R. Federman , D. E. Welty , A. M. Ritchey

We selected 90 massive star-forming clumps with strong N2H+, HCO+, HCN, and HNC emission from the Millimetre Astronomy Legacy Team 90 GHz survey. We obtained Herschel data for all 90 sources and NRAO VLA Sky Survey data for 51 of them. We…

星系天体物理 · 物理学 2019-07-25 Mingyue Li , Jianjun Zhou , Jarken Esimbek , Donghui Quan , Yuxin He , Qiang Li , Chunhua Zhu

We present spectroscopic observations of the runaway reddened star HD 34078 acquired during the last three years at Observatoire de Haute Provence and McDonald Observatory as well as other spectra obtained since 1990. The drift of the line…

天体物理学 · 物理学 2009-11-07 E. Rollinde , P. Boisse , S. R. Federman , K. Pan

We analyze a complete sample of gamma-ray burst afterglows, and find X-ray evidence for high column densities of gas around them. The column densities are in the range 1e+22-1e+23/cm2, which is right around the average column density of…

天体物理学 · 物理学 2009-10-31 Titus J. Galama , Ralph A. M. J. Wijers

Interstellar dust plays a central role in shaping the detailed structure of the interstellar medium, thus strongly influencing star formation and galaxy evolution. Dust extinction provides one of the main pillars of our understanding of…

We present high-resolution observations of interstellar CN, CH, CH^{+}, \ion{Ca}{1}, and \ion{Ca}{2} absorption lines toward the multiple star systems HD206267 and HD217035. Substantial variations in CN absorption are observed among three…

天体物理学 · 物理学 2009-11-07 K. Pan , S. R. Federman , D. E. Welty

By employing two different spectroscopic techniques we have mapped out the variable ISM dust extinction endemic to globular cluster M4. We derive an average E(B-V) reddening of 0.33 +/- 0.01 and R = 3.4 +/- 0.4, both in good agreement with…

天体物理学 · 物理学 2007-05-23 I. I. Ivans , C. Sneden , R. P. Kraft , N. B. Suntzeff , V. V. Smith , G. E. Langer , J. P. Fulbright

Observations of interstellar extinction and polarization indicate that the interstellar medium consists of aligned non-spherical dust grains which show variation in the interstellar extinction curve for wavelengths ranging from NIR to UV.…

天体物理学 · 物理学 2009-09-15 Ranjan Gupta , Tadashi Mukai , D. B. Vaidya , Asoke K. Sen , Yasuhiko Okada

Polarized extinction and emission from dust in the interstellar medium (ISM) are hard to interpret, as they have a complex dependence on dust optical properties, grain alignment and magnetic field orientation. This is particularly true in…

星系天体物理 · 物理学 2017-05-24 Lapo Fanciullo , Vincent Guillet , François Boulanger , Anthony Jones

We characterise the relation between the gas and dust content of the interstellar medium towards young stellar objects in the Orion Nebula Cluster. X-ray observations provide estimates of the absorbing equivalent hydrogen column density N_H…

太阳与恒星天体物理 · 物理学 2016-08-31 Birgit Hasenberger , Jan Forbrich , Joao Alves , Scott Wolk , Stefan Meingast , Konstantin Getman , Ignazio Pillitteri

We probe the role of carbon in the ultraviolet (UV) extinction by examining the relations between the amount of carbon required to be locked up in dust [C/H]_dust with the 2175 Angstrom extinction bump and the far-UV extinction rise, based…

星系天体物理 · 物理学 2015-08-19 Ajay Mishra , Aigen Li

Using UV spectra obtained with FUSE, HST, and/or IUE, we determine interstellar column densities of 12CO, 13CO, and/or C_2 for ten Galactic sight lines with 0.37<E(B-V)<0.72. The N(CO)/N(H_2) ratio varies over a factor of 100 in this…

天体物理学 · 物理学 2009-05-29 P. Sonnentrucker , D. E. Welty , J. A. Thorburn , D. G. York

Aims. We model a diffuse molecular cloud present along the line of sight to the star HD 102065. We compare our modeling with observations to test our understanding of physical conditions and chemistry in diffuse molecular clouds. Methods.…

Recent interstellar detections include a significant number of molecules containing vinyl (C2H3) and ethyl (C2H5) groups in their structure. For several of these molecules, there is not a clear experimental or theoretical evidence that…

星系天体物理 · 物理学 2022-09-07 German Molpeceres , Victor M. Rivilla

We have studied the interstellar extinction in a field of 3' x 3' located about 6' SW of 30 Doradus in the Large Magellanic Cloud (LMC). Hubble Space Telescope observations in the U, B, V, I and Halpha bands reveal patchy extinction in this…

太阳与恒星天体物理 · 物理学 2015-06-17 Guido De Marchi , Nino Panagia , Leo Girardi