English
Related papers

Related papers: Modelling the 1.8 MeV Sky: Tests for Spiral Struct…

200 papers

We present accurate absolute astrometry of 6.7 GHz methanol masers detected in the Arecibo Methanol Maser Galactic Plane Survey using MERLIN and the Expanded Very Large Array (EVLA). We estimate the absolute astrometry to be accurate to…

Solar and Stellar Astrophysics · Physics 2015-05-27 J. D. Pandian , E. Momjian , Y. Xu , K. M. Menten , P. F. Goldsmith

We present 1.3 millimeter ALMA Cycle 0 observations of the edge-on debris disk around the nearby, ~10 Myr-old, M-type star AU Mic. These observations obtain 0.6 arcsec (6 AU) resolution and reveal two distinct emission components: (1) the…

The GLIMPSE (Galactic Legacy Mid-Plane Survey Extraordinaire) Point Source Catalog of ~ 30 million mid-infrared sources towards the inner Galaxy, 10 < |l| < 65 degrees and |b| < 1 degree, was used to determine the distribution of stars in…

We report the discovery of a widespread population of collisionally excited methanol J = 4_{-1} to 3$_0 E sources at 36.2 GHz from the inner 66'x18' (160x43 pc) of the Galactic center. This spectral feature was imaged with a spectral…

Astrophysics of Galaxies · Physics 2015-06-12 F. Yusef-Zadeh , W. Cotton , S. Viti , M. Wardle , M. Royster

Gravitational forces are expected to excite spiral density waves in protoplanetary disks, disks of gas and dust orbiting young stars. However, previous observations that showed spiral structure were not able to probe disk midplanes, where…

Various theoretical models predict the existence of extended $\gamma$-ray halo around normal galaxies that could be produced by interactions of cosmic rays with the circumgalactic medium or by annihilation or decay of hypothetical dark…

High Energy Astrophysical Phenomena · Physics 2026-04-03 M. S. Pshirkov , B. A. Nizamov

The properties of the galaxy distribution at large scales are usually studied using statistics which are assumed to be self-averaging inside a given sample. We present a new analysis able to quantitatively map galaxy large scale structures…

We use surface brightness contour maps of nearby edge-on spiral galaxies to determine whether extended bright radio halos are common. In particular, we test a recent model of the spatial structure of the diffuse radio continuum by…

Astrophysics of Galaxies · Physics 2015-06-23 J. Singal , A. Kogut , E. Jones , H. Dunlap

The formation mechanism of the hot gaseous halo associated with the Milky Way Galaxy is still under debate. We report new observational constraints on the gaseous halo using 107 lines-of-sight of the Suzaku X-ray observations at…

Astrophysics of Galaxies · Physics 2018-08-08 Shinya Nakashima , Yoshiyuki Inoue , Noriko Yamasaki , Yoshiaki Sofue , Jun Kataoka , Kazuhiro Sakai

The mass distribution of the Galactic disk is constructed from the terminal velocity curve and the mass discrepancy-acceleration relation. Mass models numerically quantifying the detailed surface density profiles are tabulated. For $R_0 =…

Astrophysics of Galaxies · Physics 2016-01-13 Stacy S. McGaugh

Recently, the SPI spectrometer on the INTEGRAL satellite observed strong 511 keV line emission from the galactic bulge. Although the angular distribution (spherically symmetric with width of \sim 9 degree) of this emission is difficult to…

High Energy Physics - Phenomenology · Physics 2009-11-10 Dan Hooper , Lian-Tao Wang

The spectrometer SPI on INTEGRAL allows for the first time simultaneous imaging of diffuse and point-like emission in the hard X-ray and soft gamma-ray regime. To fully exploit the capabilities of the instrument, we implemented the MREM…

The annihilation of positrons in the Galaxy's interstellar medium produces characteristic gamma-rays with a line at 511 keV. This emission has been observed with the spectrometer SPI on INTEGRAL, confirming a puzzling morphology with bright…

Context. Research over the past three decades has revolutionized cosmology while supporting the standard cosmological model. However, the cosmological principle of Universal homogeneity and isotropy has always been in question, since…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-08 Istvan Horvath , Jon Hakkila , Zsolt Bagoly

We report the first results from high-statistics observation of the 6.4-keV line in the region of $l= +1.5^\circ$ to $+3.5^\circ$ (hereafter referred to as GC East), with the goal to uncover the origin of the Galactic ridge X-ray emission…

High Energy Astrophysical Phenomena · Physics 2014-08-04 T. G. Tsuru , H. Uchiyama , K. K. Nobukawa , M. Nobukawa , S. Nakashima , K. Koyama , K. Torii , Y. Fukui

The center of our Galaxy is a known strong source of electron-positron 511-keV annihilation radiation. Thus far, however, there have been no reliable detections of annihilation radiation outside of the central radian of our Galaxy. One of…

Sensitive ground-based submillimeter surveys, such as ATLASGAL, provide a global view on the distribution of cold dense gas in the Galactic plane. Here we use the 353 GHz maps from the Planck/HFI instrument to complement the ground-based…

Solar and Stellar Astrophysics · Physics 2016-01-13 T. Csengeri , A. Weiss , F. Wyrowski , K. M. Menten , J. S. Urquhart , S. Leurini , F. Schuller , H. Beuther , S. Bontemps , L. Bronfman , Th. Henning , N. Schneider

A mid-infrared (3.6-8 um) survey of the Galactic Center has been carried out with the IRAC instrument on the Spitzer Space Telescope. This survey covers the central 2x1.4 degree (~280x200 pc) of the Galaxy. At 3.6 and 4.5 um the emission is…

We have used the VLA to detect emission from the supergiant VY CMa at radio wavelengths and have constructed 3000-4500 K isothermal outer atmospheres constrained by the data. These models produce a radio photosphere at 1.5-2 R_ast. An…

Astrophysics · Physics 2009-11-10 S. J. Lipscy , M. Jura , M. J. Reid

We consider seven distant galaxies with clearly evident spiral structure from HST images. Three of these were chosen from Vogt et al. (1996) (VFP) and have measured rotational velocities. Five were chosen from the Medium Deep Survey and are…

Astrophysics · Physics 2009-10-30 A. C. Quillen , V. L. Sarajedini