相关论文: Distance of PSR B0458+46 indicated by FAST HI abso…
We present 92cm observations of the high-redshift galaxy B2 0902+343 (z=3.40) with the Westerbork Synthesis Radio Telescope (WSRT). Twenty-one cm HI is detected in absorption, at a depth of 15.9 mJy (=~6\sigma) and rest frame velocity width…
We report the first detection of optical emission from the shell-type Galactic supernova remnant (SNR) G108.2$-$0.6. We obtained H$\alpha$ images and long-slit spectra using the 1.5-m RTT150 telescope to examine the morphological and…
Underlying nearly every quantitative discussion of the Cygnus Loop supernova remnant is uncertainty about its distance. Here we present optical images and spectra of nebulosities around two stars whose mass-loss material appears to have…
We have measured the distance to the massive star-forming region W3OH in the Perseus spiral arm of the Milky Way to be 1.95 $\pm$ 0.04 kilo-parsecs ($5.86\times10^{16}$ km). This distance was determined by triangulation, with the Earth's…
Kinematic distances to 750 molecular clouds identified in the 13CO J=1-0 Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey (BU-FCRAO GRS) are derived assuming the Clemens rotation curve of the Galaxy. The…
The youngest known Galactic supernova remnant (SNR) G1.9+0.3 has high-velocity supernova shock beyond 10000 km s-1, and it is considered to be one of the major candidates of a PeVatron. Despite these outstanding properties, the surrounding…
As part our investigation into the Galactic rotation curve, we carried out Very Long Baseline Interferometry (VLBI) observations towards the star-forming region IRAS 01123+6430 using VLBI Exploration of Radio Astrometry (VERA) to measure…
We use the Expanding Photosphere Method to determine distances to 10 type II supernovae. The effects of asymmetries, extinction, and flux dilution are explored. Using empirical evidence and time-independent, spherical models which treat H…
We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for PSR B1509-58, with a 2 sigma upper limit…
We report a new geometric maser distance estimate to the active galaxy NGC 4258. The data for the new model are maser line-of-sight velocities and sky positions from 18 epochs of Very Long Baseline Interferometry observations, and…
We present a measurement of the proper motion of the presumed pulsar in the evolved composite supernova remnant (SNR) MSH 15-56 whose pulsar wind nebula (PWN) has been disrupted by the supernova (SN) reverse shock. Using Chandra X-ray…
Using pairs of images from the Chandra High-Resolution Camera we examine the proper motion of the central compact object (CCO) 1E 1207.4-5209 in the supernova remnant (SNR) PKS 1209-51/52, and the unusual pulsar Calvera that is possibly a…
We report trigonometric parallax and proper motion measurements of 6.7-GHz CH3OH and 22-GHz H2O masers in eight high-mass star-forming regions (HMSFRs) based on VLBA observations as part of the BeSSeL Survey. The distances of these HMSFRs…
We report the detection using ASCA data of a hard X-ray source in the vicinity of the radio pulsar PSR B1853+01 which is located within the supernova remnant (SNR) W44. PSR B1853+01, a 267ms pulsar, has to date only been detected in the…
The longitude separation between adjacent drifting subpulses, $P_2$, is roughly constant for many pulsars. It was then perplexing when pulsar B0809+74 was found to exhibit substantial variations in this measure, both with wavelength and…
We measure the proper motion of the pulsar PSR J1745-2900 relative to the Galactic Center massive black hole, Sgr A*, using the Very Long Baseline Array (VLBA). The pulsar has a transverse velocity of 236 +/- 11 km s^-1 at position angle 22…
A combination of archival multi-frequency radio observations with narrow-band HAlpha optical imagery and new confirmatory optical spectroscopy have shown that candidate supernova remnant G6.31+0.54 can now be confirmed as part of a Galactic…
In Yoshii et al. (2014), we described a new method for measuring extragalactic distances based on dust reverberation in active galactic nuclei (AGNs), and we validated our new method with Cepheid variable stars. In this paper, we validate…
HESS J1858+020 is a weak gamma-ray source that does not have any clear cataloged counterpart at any wavelengths. Recently, the source G35.6-0.4 was re-identified as a SNR. The HESS source lies towards the southern border of this remnant.…
The pulsar PSR J1756$-$2251 resides in a relativistic double neutron star (DNS) binary system with a 7.67-hr orbit. We have conducted long-term precision timing on more than 9 years of data acquired from five telescopes, measuring five…