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Related papers: HCO+ and HCN J=3-2 absorption toward the center of…

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We recently reported a population of protostellar candidates in the 20 km s$^{-1}$ cloud in the Central Molecular Zone of the Milky Way, traced by H$_2$O masers in gravitationally bound dense cores. In this paper, we report…

We report deep K-band (18-27GHz) observations with the 100-m Green Bank Telescope of HCN(1-0) line emission towards the two submillimeter-selected galaxies (SMGs) SMMJ02399-0136 (z=2.81) and SMMJ16359+6612 (z=2.52). For both sources we have…

Astrophysics · Physics 2016-08-15 T. R. Greve , L. J. Hainline , A. W. Blain , Ian Smail , R. J. Ivison , P. P. Papadopoulos

We report the detection, for the first time, of HCO+ (J=1-0) emission as well as marginal CO (J=1-0) emission toward the planetary nebula (PN) K3-35 as a result of a molecular survey carried out toward this source. We also report new…

We investigate the relationship between CN N = 1 - 0 and HCN J = 1 - 0 emission on scales from 30 pc to 400 pc using ALMA archival data, for which CN is often observed simultaneously with the CO J = 1 - 0 line. In a sample of 9 nearby…

Astrophysics of Galaxies · Physics 2023-03-15 Christine D. Wilson , Ashley Bemis , Blake Ledger , Osvald Klimi

We report a sensitive search for the HCN(J=2-1) emission line towards SDSS J1148+5251 at z=6.42 with the VLA. HCN emission is a star formation indicator, tracing dense molecular hydrogen gas (n(H2) >= 10^4 cm^-3) within star-forming…

Astrophysics · Physics 2008-07-12 Dominik A. Riechers , Fabian Walter , Christopher L. Carilli , Frank Bertoldi

We surveyed 81 dense molecular cores associated with regions of massive star formation and Sgr A in the 5_{05}-4_{04} and 10_{010}-9_{09} lines of HNCO. Line emission was detected towards 57 objects. Selected subsamples were also observed…

Astrophysics · Physics 2007-05-23 I. Zinchenko , C. Henkel , R. Q. Mao

With the incorporation of high-J molecular lines, we aim to constrain the physical conditions of the dense gas in the central region of the Seyfert 2 galaxy NGC 1068 and to determine signatures of the AGN or the starburst contribution. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. P. Perez-Beaupuits , M. Spaans , F. F. S. van der Tak , S. Aalto , S. Garcia-Burillo , A. Fuente , A. Usero

We have observed 6 clouds along the line-of-sight toward W49A using the Submillimeter Wave Astronomy Satellite (SWAS) and several ground-based observatories. The ortho-H2O 1-0 and OH (1665 and 1667 MHz) transitions are observed in…

Supernova remnants act as particle accelerators, providing the cosmic-ray protons that permeate the interstellar medium and initiate the ion-molecule reactions that drive interstellar chemistry. Enhanced fluxes of cosmic-ray protons in…

High Energy Astrophysical Phenomena · Physics 2023-06-13 Nick Indriolo

We performed a systematic analysis of the 4.67 $\mu$m CO ro-vibrational absorption band toward nearby active galactic nuclei (AGNs) and analyzed the absorption profiles of ten nearby galaxies collected from the AKARI and Spitzer…

Astrophysics of Galaxies · Physics 2018-01-24 S. Baba , T. Nakagawa , N. Isobe , M. Shirahata

We explore the potential of imaging vibrationally excited molecular emission at high angular resolution to better understand the morphology and physical structure of the dense gas in Arp~220 and to gain insight into the nature of the…

We present results from a spectroscopically blind search for associated and intervening HI 21-cm and OH 18-cm absorption lines towards 88 AGNs at $2\le z\le5$ using the upgraded Giant Metrewave Radio Telescope (uGMRT). The sample of AGNs…

We present the results of a recently conducted mm-experiment at the IRAM 30m telescope. We searched in two QSO hosts for the HCN(J=1-0) line emission tracing the dense regions of gas. Our goal is to probe the HCN-CO line ratio in QSO hosts…

Astrophysics · Physics 2009-11-11 J. -U. Pott , A. Eckart , M. Krips , L. Tacconi-Garman , E. Lindt

Context: We investigated the molecular gas associated with 6.7 GHz methanol masers throughout the Galaxy using a J=1-0 transition of the CO isotopologues. Methods:Using the 13.7-meter telescope at the Purple Mountain Observatory (PMO), we…

Solar and Stellar Astrophysics · Physics 2014-09-05 Zhiyuan Ren , Yuefang Wu , Tie Liu , Lixin Li , Di Li , Binggang Ju

The cold molecular gas in the circumnuclear disk (CND) of radio galaxies provides critical information for understanding the mass accretion onto active galactic nuclei. We present the first detection and maps of HCN J=1-0 and HCO+ J=1-0…

Astrophysics of Galaxies · Physics 2022-08-17 Satoko Sawada-Satoh , Seiji Kameno , Sascha Trippe

We present the results of a survey for HI 21-cm and OH 18-cm absorption in seven strong CO emitters at z > 3. Despite reaching limits comparable to those required to detect 21-cm absorption at lower redshifts, we do not detect either…

Astrophysics of Galaxies · Physics 2016-03-16 S. J. Curran , J. R. Allison , M. T. Whiting , E. M. Sadler , F. Combes , M. B. Pracy , C. Bignell , R. Athreya

Stars form out of the densest parts of molecular clouds. Far-IR emission can be used to estimate the Star Formation Rate (SFR) and high dipole moment molecules, typically HCN, trace the dense gas. A strong correlation exists between HCN and…

Astrophysics of Galaxies · Physics 2016-12-28 J. Braine , Y. Shimajiri , P. André , S. Bontemps , Yu Gao , Hao Chen , C. Kramer

Using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) the COS Science Team has conducted a high signal-to-noise survey of 14 bright QSOs. In a previous paper (Savage et al. 2014) these far-UV spectra were used to…

We report the results of our observations of HI absorption towards the central region of the rejuvenated radio galaxy 4C29.30 (J0840+2949) with the Giant Metrewave Radio Telescope (GMRT). The radio source has diffuse, extended emission with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Yogesh Chandola , D. J. Saikia , Neeraj Gupta

We report the detection of HCO+(5-4) emission from the Broad Absorption Line (BAL) quasar APM08279+5255 at z=3.911 based on observations conducted at the IRAM Plateau de Bure interferometer. This represents the first detection of this…