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Related papers: On the frequency of N2H+ and N2D+

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We report on the detection of the ground-state rotational line of ortho-D2H+ at 1.477 THz (203 micron) using the German REceiver for Astronomy at Terahertz frequencies (GREAT) onboard the Stratospheric Observatory For Infrared Astronomy…

(abridged) We have mapped the prestellar core H-MM1 in Ophiuchus in rotational lines of ortho-H2D+ (oH2D+), N2H+, and DCO+ at the wavelength 0.8 mm with the Large APEX sub-Millimeter Array (LAsMA) multibeam receiver of the Atacama…

To investigate how the abundance of N2H+ varies as massive clumps evolve, here we present a multi-wavelength study toward six molecular clouds. All of these clouds contain several massive clumps in different evolutionary stages of star…

Astrophysics of Galaxies · Physics 2019-05-23 Nai-Ping Yu , Jin-Long Xu , Jun-Jie Wang , Xiao-Lan Liu

The excitation temperature T_01 derived from the relative intensities of the J = 0 (para) and J = 1 (ortho) rotational levels of H2 has been assumed to be an accurate measure of the kinetic temperature in interstellar environments. In…

Astrophysics of Galaxies · Physics 2015-05-27 Kyle N. Crabtree , Nick Indriolo , Holger Kreckel , Brian A. Tom , Benjamin J. McCall

We present new radio-frequency interferometric maps of emission from the 14NH3, 15NH3, and 14NH2D isotopologues of ammonia, and the 12CH3OH and 13CH3OH isotopologues of methanol toward Sgr B2(N). With a resolution of ~3'' (0.1 pc), we are…

Astrophysics of Galaxies · Physics 2018-12-26 E. A. C. Mills , J. Corby , A. R. Clements , N. Butterfield , P. Jones , M. Cunningham , J. Ott

The inclusive e^+ p single and double differential cross sections for neutral and charged current processes are measured with the H1 detector at HERA. The data were taken in 1999 and 2000 at a centre-of-mass energy of \sqrt{s} = 319 GeV and…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

Deuteration is sensitive to environmental conditions in star-forming regions. To investigate NH$_2$D chemistry, we compared the spatial distribution of ortho-NH$_2$D $1_{11}^s-1_{01}^a$, NH$_3$(1,1) and NH$_3$(2,2) in 12 late-stage massive…

Astrophysics of Galaxies · Physics 2024-11-28 Yuqiang Li , Junzhi Wang , Juan Li , Prathap Rayalacheruvu , Liton Majumdar , Yaoting Yan , Donghui Quan , Xing Lu , Siqi Zheng

We report precision atmospheric spectroscopy of $CO_2$ using a laser heterodyne radiometer (LHR) calibrated with an optical frequency comb. Using the comb-calibrated LHR, we record spectra of atmospheric $CO_2$ near 1572.33 nm with a…

Optics · Physics 2023-10-03 Ryan K. Cole , Connor Fredrick , Newton H. Nguyen , Scott A. Diddams

We used the APEX telescope to observe the 372 GHz o-H$_2$D$^+(J_{K_a,\,K_c}=1_{1,\,0}-1_{1,\,1})$ line towards three prestellar cores and three protostellar cores in Orion B9. We also employed our previous APEX observations of C$^{17}$O,…

Astrophysics of Galaxies · Physics 2020-02-19 Oskari Miettinen

Using microwave detected, microwave-optical double resonance, we have measured the homogeneous linewidths of individual rovibrational transitions in the \~A state of NH3, NH2D, NHD2, and ND3. We have used this excited state spectroscopic…

Supernova remnants (SNRs) may regulate star formation in galaxies. For example, SNR-driven shocks may form new molecular gas or compress pre-existing clouds and trigger the formation of new stars. To test this scenario, we measure the…

We investigate the finite nuclear mass corrections in the helium atom in order to resolve a significant disagreement between the $2^3S - 2^3P$ and $2^3S - 2^1S$ transition isotope shifts. These two transitions lead to discrepant results for…

Atomic Physics · Physics 2017-01-31 V. Patkos , V. A. Yerokhin , K. Pachucki

The cross section and the proton structure function F2 for neutral current deep inelastic e+p scattering have been measured with the ZEUS detector at HERA using an integrated luminosity of 30 pb-1. The data were collected in 1996 and 1997…

High Energy Physics - Experiment · Physics 2012-08-27 ZEUS Collaboration

We improve by a factor of 4-20 the energy accuracy of the strongest soft X-ray transitions of Fe XVII ions by resonantly exciting them in an electron beam ion trap with a monochromatic beam at the P04 beamline of the PETRA III synchrotron…

We present sensitive observations of NH2D at 110.153599 GHz toward 50 Galactic massive star-forming regions with IRAM 30-m telescope. The NH2D transition is detected toward 36 objects, yielding a detection rate of 72%. Column densities of…

Astrophysics of Galaxies · Physics 2022-04-27 Yuqiang Li , Junzhi Wang , Juan Li , Shu Liu , Qiuyi Luo

A cubic kilometer scale experiment has been proposed to detect cosmic neutrinos of energy from tens of GeV up to the highest energies observed for cosmic rays, around 10**20 eV, or possibly even beyond. Detection efficiencies depend…

High Energy Physics - Phenomenology · Physics 2009-10-30 Guenter Sigl

Accurate measurements of different transition frequencies between atomic levels of the electronic and hyperfine structure over time are used to investigate temporal variations of the fine structure constant $\alpha$ and the…

Atomic Physics · Physics 2014-12-01 N. Huntemann , B. Lipphardt , Chr. Tamm , V. Gerginov , S. Weyers , E. Peik

In this work we describe the latest results for the measurements of the hyperfine structure of antiprotonic helium-3. Two out of four measurable super-super-hyperfine SSHF transition lines of the (n,L)=(36,34) state of antiprotonic helium-3…

To investigate whether distinctions exist between low and high-luminosity Class II 6.7-GHz methanol masers, we have undertaken multi-line mapping observations of various molecular lines, including the NH3(1,1), (2,2), (3,3), (4,4) and…

Astrophysics of Galaxies · Physics 2010-07-13 Y. W. Wu , Y. Xu , J. D. Pandian , J. Yang , C. Henkel , K. M. Menten , S. B. Zhang

Inclusive jet differential cross sections for the reaction e+ p --> e+ + jet + X with quasi-real photons have been measured with the ZEUS detector at HERA. These cross sections are given for the photon-proton centre-of-mass energy interval…

High Energy Physics - Experiment · Physics 2012-08-27 ZEUS Collaboration
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