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Related papers: H2 Temperatures in the Crab Nebula

200 papers

We report the discovery of giant (50-100 kpc) [O II] emitting nebulae with the Multi-Unit Spectroscopic Explorer (MUSE) in the field of TXS 0206-048, a luminous quasar at z=1.13. Down-the-barrel UV spectra of the quasar show absorption at…

The Crab supernova remnant has been observed regularly with the stereoscopic system of 5 imaging air Cherenkov telescopes that was part of the High Energy Gamma Ray Astronomy (HEGRA) experiment. In total, close to 400 hours of useful data…

Astrophysics · Physics 2010-01-28 F. Aharonian et al.

Ground state rotational lines of H2 are good temperature probes of moderately hot (200-1000 K) gas. The low A-values of these lines result in low critical densities while ensuring that the lines are optically thin. ISO observations of H2…

Astrophysics · Physics 2009-11-10 Katelyn N. Allers , Daniel T. Jaffe , John H. Lacy , Matthew J. Richter

From existing broad-band images obtained with the Hubble Space Telescope, we located 92 globules, for which we derived positions, dimensions, orientations, extinctions, masses, proper motions, and their distributions. The globules have mean…

Solar and Stellar Astrophysics · Physics 2017-03-15 Tiia Grenman , Gösta F. Gahm , Erik Elfgren

We report the first detection of HS2 towards the cold dark cloud TMC-1. This is the first observation of a chemical species containing more than one sulphur atom in this type of sources. The astronomical observations are part of QUIJOTE, a…

Astrophysics of Galaxies · Physics 2025-06-17 G. Esplugues , M. Agúndez , G. Molpeceres , B. Tercero , C. Cabezas , N. Marcelino , R. Fuentetaja , J. Cernicharo

The kinematics, shaping, density distribution, expansion distance, and ionized mass of the nebula Hen 2-104, and the nature of its symbiotic Mira are investigated. A combination of multi-epoch HST images and VLT integral field…

We present Wisconsin H-Alpha Mapper observations of ionized gas in the Smith Cloud, a high velocity cloud which Lockman et al. have recently suggested is interacting with the Galactic disk. Our H-alpha map shows the brightest H-alpha…

Astrophysics of Galaxies · Physics 2009-09-17 Alex S. Hill , L. Matthew Haffner , Ronald J. Reynolds

Broad-band images of the solar chromosphere in the Ca II H&K line cores around active regions are covered with fine bright elongated structures called bright fibrils. The mechanisms that form these structures and cause them to appear bright…

Solar and Stellar Astrophysics · Physics 2020-05-06 Sepideh Kianfar , Jorrit Leenaarts , Sanja Danilovic , Jaime de la Cruz Rodríguez , Carlos José Díaz Baso

The Crab Pulsar's radio emission is unusual, consisting predominantly of giant pulses, with durations of about a micro-second but structure down to the nano-second level, and brightness temperatures of up to $10^{37}\,$K. It is unclear how…

The Crab Nebula is used by many instruments as a calibration source, in particular at high energy, where it is one of the brightest celestial object. The spectrometer INTEGRAL SPI (20 keV - 8 MeV), in operation since October 2002, offers a…

High Energy Astrophysical Phenomena · Physics 2020-09-02 E. Jourdain , J. P. Roques

We present the results of a systematic search for molecular hydrogen (H2) in low redshift ($ 0.05 \lesssim z \lesssim 0.7$) DLAs and sub-DLAs with $N(HI) \gtrsim 10^{19.0}$ cm$^{-2}$, in the archival HST/COS spectra. Our core sample is…

Astrophysics of Galaxies · Physics 2015-03-10 Sowgat Muzahid , Raghunathan Srianand , Jane Charlton

We present a spectral line analysis of the hot molecular core G10.47+0.03 (hereafter, G10). Our aim is to determine molecular abundances and excitation conditions across a wide spectral range inaccessible to ground-based observatories. We…

The complex conductivity of a MgB2 film has been investigated in the frequency range 4 cm^{-1}< nu < 30 cm^{-1} and for temperatures 2.7 K < T <300 K. The overall temperature dependence of both components of the complex conductivity is…

Superconductivity · Physics 2009-11-07 A. V. Pronin , A. Pimenov , A. Loidl , S. I. Krasnosvobodtsev

We report the detection of a complex of extraplanar warm H_2 knots and filaments extending more than ~3 kpc above and below the galactic plane of M82, roughly coincident with the well-known galactic wind in this system. Comparisons of these…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 S. Veilleux , D. S. N. Rupke , R. Swaters

We outline a model of the Crab Pulsar Wind Nebula with two different populations of synchrotron emitting particles, arising from two different acceleration mechanisms: (i) Component-I due to Fermi-I acceleration at the equatorial portion of…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Maxim Lyutikov , Tea Temim , Sergey Komissarov , Patrick Slane , Lorenzo Sironi , Luca Comisso

Gamma rays with energies greater than 7 TeV from the Crab pulsar/nebula have been observed at large zenith angles, using the Imaging Atmospheric Technique from Woomera, South Australia. CANGAROO data taken in 1992, 1993 and 1995 indicate…

The Crab nebula is a prominent pulsar wind nebula (PWN) detected in multiband observations ranging from radio to very high-energy (VHE) $\gamma$-rays. Recently, $\gamma$-rays with energies above $1 \mathrm{PeV}$ had been detected by the…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Lu Wen , Ke-Yao Wu , Huan Yu , Jun Fang

We have observed the S(0), S(1), S(2), S(3), S(4) and S(5) rotational lines of molecular hydrogen (H2) towards the peak of the photodissociation region (PDR) associated with the reflection nebula NGC 7023. The observed H2 line ratios show…

We report medium resolution VLT ISAAC K-band spectroscopy of the nuclei of seven ultraluminous infrared galaxies. After accounting for stellar absorption features, we have detected several molecular hydrogen (H_2) v=1-0, 2-1, and 3-2…

Astrophysics · Physics 2009-11-10 R. I. Davies , A. Sternberg , M. Lehnert , L. E. Tacconi-Garman

We present medium resolution (1000) K-band spectra of 12 post-AGB candidates and related stars. For several objects in our sample, these spectra were obtained for the first time. The Br$\gamma$ line in emission is detected in seven objects…

Solar and Stellar Astrophysics · Physics 2020-08-26 M. Parthasarathy , C. Muthumariappan , S. Muneer