A5101733537- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Spectroscopy and Laser Applications
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Atmospheric Ozone and Climate
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Atomic and Molecular Physics
- Astronomical Observations and Instrumentation
- Molecular Spectroscopy and Structure
- Laser Design and Applications
- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Scientific Research and Discoveries
- Particle Accelerators and Free-Electron Lasers
- Cosmology and Gravitation Theories
- Photochemistry and Electron Transfer Studies
- Advanced Chemical Physics Studies
- Superconducting and THz Device Technology
- Atmospheric and Environmental Gas Dynamics
- Phase Equilibria and Thermodynamics
- Advanced Combustion Engine Technologies
- Inorganic Fluorides and Related Compounds
- Photocathodes and Microchannel Plates
Catholic University of America
2016-2021
University of America
2016-2021
Atacama Large Millimeter Submillimeter Array
2014
Space Telescope Science Institute
2005-2011
National Observatory
1987-2010
Swedish Institute of Space Physics
1989-2008
Chalmers University of Technology
1993-2007
European Space Agency
1997
Université de Versailles Saint-Quentin-en-Yvelines
1993
Sorbonne Université
1993
We present high resolution large scale observations of the molecular and atomic gas in Local Group Galaxy M33. The were carried out using HERA at 30m IRAM telescope CO(2-1) line achieving a 12"x2.6 km/s, enabling individual GMCs to be resolved. observed region mainly along major axis radius 8.5 kpc, covers strip with HIFI/PACS Spectrometers as part HERM33ES Herschel key program. achieved sensitivity main beam temperature is 20-50 mK 2.6 km/s velocity resolution. luminosity 1.7\pm0.1x10^7...
Context.Molecular oxygen, O2, has been expected historically to be an abundant component of the chemical species in molecular clouds and, as such, important coolant dense interstellar medium. However, a number attempts from both ground and space have failed detect O2 emission.
We have detected the four 18 cm OH lines from $z\ensuremath{\sim}0.765$ gravitational lens toward PMN J0134--0931. The 1612 and 1720 MHz are in conjugate absorption emission, providing a laboratory to test evolution of fundamental constants over large lookback time. compare HI main line redshifts different components absorber $z\ensuremath{\sim}0.685$ $\mathrm{B}0218+357$ place stringent constraints on changes...
We present the first results of an ALMA spectral survey strong absorption lines for common interstellar species in z = 0.89 molecular absorber toward lensed blazar PKS 1830−211. The dataset brings essential information on structure and composition absorbing gas foreground galaxy. In particular, we find over large velocity intervals (≳100 km s-1) both images blazar. This suggests either that galaxy inclination is intermediate sample gradients or streaming motions disk plane, has a vertical...
Quasar (QSO) absorption spectra provide an extremely useful probe of possible cosmological variation in various physical constants. Comparison H i 21-cm with corresponding molecular (rotational) allows us to constrain , where α is the fine-structure constant and gp proton g-factor. We analyse two QSOs, PKS 1413+135 TXS 0218+357, derive values at redshifts 0.6847 by simultaneous fitting lines. find respectively, indicating insignificantly smaller y past. compare our results other constraints...
New single-dish and millimeter wave interferometer observations of the molecular absorption line system in gravitational lens to PKS 1830-211 at z = 0.88582 are presented. Self-calibrated data show unequivocally that previously detected component is associated with gravitationally lensed southwest image background source. A second HCO+ (2←1) detected. This shifted velocity by -147 km s-1 relative main shown be northeast image. few additional lines Upper limits emission from possible 0.1927,...
We report the detection of OH+ and H2O+ in z=0.89 absorber toward lensed quasar PKS1830-211. The abundance ratio is used to quantify molecular hydrogen fraction (fH2) cosmic-ray ionization rate atomic (zH) along two lines sight, located at ~2 kpc ~4 either side absorber's center. decreases outwards, from ~0.04 ~0.02, comparable values measured Milky Way similar galactocentric radii. For zH, we find ~2x10^-14 s^-1 ~3x10^-15 s^-1, respectively, which are slightly higher than radii, possibly...
We present the results of a z>2.9 survey for HI 21-cm and molecular absorption in hosts radio quasars using GMRT Tidbinbilla 70-m telescope. Previously published searches, which are overwhelmingly at redshifts z<1, exhibit 42% detection rate (31 out 73 sources), inclusion our yields 17% (2 12 sources) z>2.5. therefore believe that high redshift selection is responsible exclusive non-detections, find ultra-violet luminosities >10e23 W/Hz, has never been detected. also this to not only apply...
We report the detection of H_2O molecule in absorption at a redshift z = 0.68466 front gravitationally lensed quasar B0218+357. detect fundamental transition ortho-water 556.93 GHz (redshifted to 330.59 GHz). The line is highly optically thick and relatively wide (15 km/s FWHM), with profile that similar previously detected CO(2--1) HCO^+(2--1) lines toward this quasar. From measured level continuum GHz, which corresponds expected from power-law spectrum $S(\nu) \propto \nu^{-0.25}$ already...
From a survey for redshifted HI 21-cm and OH 18-cm absorption in the hosts of sample radio galaxies quasars, we detect three ten none fourteen sources which useful data were obtained. As expected from our recent result, all detections occur with ultra-violet continuum luminosities L < 10^23 W/Hz. At these "moderate" luminosities, also obtain four non-detections, although, as confirmed by equipartition between type-1 type-2 objects, this near-50% detection rate cannot be attributed to unified...
The z=0.89 molecular absorber toward PKS1830-211 provides us with the opportunity to probe chemical and physical properties of interstellar medium in disk a galaxy at look-back time half present age Universe. Recent ALMA observations hydrides have unveiled multi-phase composition this source's along two absorbing sightlines. Here, we report CH+ SH+, their 13C- 34S- isotopologues, as potential tracers energetic processes medium. 13CH+ are detected both images PKS1830-211, showing deepest...
view Abstract Citations (42) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Molecular Absorption Lines toward the Nucleus of Centaurus A Eckart, A. ; Cameron, M. Genzel, R. Jackson, J. Rothermel, H. Stutzki, Rydbeck, G. Wiklind, T. We present measurements absorption lines ^12^CO, ^13^CO, HCO^+^, HCN, CN, and CS nuclear continuum source obtained with Swedish-ESO Submillimeter Telescope (SEST). The spectra show a number features line widths few...
We report the detection of molecular absorption lines at z=0.7645 towards radio-loud QSO PMN 0134-0931. The CO J=2-1 and HCO+ are seen in along two different sight to lensed images background QSO. separated by ~0.7", corresponding 5 kpc lens plane. 0134-0931 represents one out only five known line systems cosmologically significant distances. Moreover, it is also three such where occurs a galaxy acting as gravitational lens. through shifted 215+/-8 km/s, possibly representing rotational...
We report the detection of molecular gas in central region S0/E7 galaxy NGC 4550, inferred from observations CO(1-0) emission. Dust is detected HST WFPC2 images and found to be asymmetrically distributed around nucleus, only extending a galactocentric distance 7'' (600 pc). The shape CO emission profile consistent with distribution following dust. dust center could result an instability, which fastest growing unstable mode counterrotating stellar disks. On global scale 4550 stable against...
Star-forming dwarf galaxies have properties similar to those expected in high-redshift galaxies. Hence, these local may provide insights into the evolution of first galaxies, and physical processes at work. We present a sample eleven potential analogs high-$z$ (LAHz) The consists blue compact selected spectral energy distributions that fit $1.5<z<4$. use SOFIA-HAWC+ observations combined with optical near-infrared data characterize dust properties, star formation rate (SFR) histories (SFH)...