Search Publications
Spectra of Cosmic-Ray Sodium and Aluminum and Unexpected Aluminum Excess
Jóhannesson, G.; Moskalenko, I. V.; Porter, T. A. +11 more
Since its launch, the Alpha Magnetic Spectrometer-02 (AMS-02) has delivered outstanding quality measurements of the spectra of cosmic-ray (CR) species, $\bar{p}$ , e ±, and nuclei (H-Si, Fe), which resulted in a number of breakthroughs. The most recent AMS-02 result is the measurement of the spectra of CR sodium and aluminum up to ~2 TV…
Discovery of Year-scale Time Variability from Thermal X-Ray Emission in Tycho's Supernova Remnant
Yamaguchi, Hiroya; Uchida, Hiroyuki; Tsuru, Takeshi Go +2 more
Mechanisms of particle heating are crucial to understanding the shock physics in supernova remnants (SNRs). However, there has been little information on time variabilities of thermalized particles so far. Here, we present a discovery of a gradually brightening thermal X-ray emission found in the Chandra data of Tycho's SNR obtained during 2000-20…
Core orientations and magnetic fields in isolated molecular clouds
Soam, Archana; Lee, Chang Won; Sharma, Ekta +2 more
Molecular clouds are sites of star formation. Magnetic fields are believed to play an important role in their dynamics and shaping morphology. We aim to study any possible correlation that might exist between the magnetic fields orientation inside the clouds and the magnetic fields at envelope scales and their connection with respect to the observ…
Polarization from Aligned Dust Grains in the β Pic Debris Disk
Hughes, A. Meredith; Hull, Charles L. H.; Le Gouellec, Valentin J. M. +8 more
We present 870 µm Atacama Large Millimeter/submillimeter Array polarization observations of thermal dust emission from the iconic, edge-on debris disk β Pic. While the spatially resolved map does not exhibit detectable polarized dust emission, we detect polarization at the ~3σ level when averaging the emission across the entire disk. The cor…
An Optical Spectrum of the Diffuse Galactic Light from BOSS and IRIS
Hensley, Brandon S.; Brandt, Timothy D.; Draine, Bruce T. +2 more
We present a spectrum of the diffuse Galactic light (DGL) between 3700 and 10,000 Å, obtained by correlating optical sky intensity with far-infrared dust emission. We use nearly 250,000 blank-sky spectra from BOSS/SDSS-III together with IRIS-reprocessed maps from the IRAS satellite. The larger sample size compared to SDSS-II results in a factor-of…
Observations of cross scale energy transfer in the inner heliosphere by Parker Solar Probe
Parashar, Tulasi N.; Matthaeus, William H.
The solar wind, a continuous flow of plasma from the sun, not only shapes the near Earth space environment but also serves as a natural laboratory to study plasma turbulence in conditions that are not achievable in the lab. Starting with the Mariners, for more than five decades, multiple space missions have enabled in-depth studies of solar wind t…
In the Trenches of the Solar-Stellar Connection. VI. Total EclipSS
Buzasi, Derek; Ayres, Thomas
The Ecliptic poles Stellar Survey (EclipSS; 2018-2019) collected Hubble Space Telescope/Cosmic Origins Spectrograph (COS) 1150-1420 Å spectra of 49 FGK dwarfs at high ecliptic latitudes. These regions are favored by the scanning programs of the Transiting Exoplanet Survey Satellite (TESS; high-precision optical light curves) and Extended Roentgen …
Regular radial velocity variations in nine G- and K-type giant stars: Eight planets and one planet candidate
Izumiura, Hideyuki; Sato, Bun'ei; Yoshida, Michitoshi +9 more
We report the detection of radial velocity (RV) variations in nine evolved G- and K-type giant stars. The observations were conducted at Okayama Astrophysical Observatory. Planets or planet candidates can best explain these regular variations. However, a coincidence of near 280 d variability among five of them prevents us from fully ruling out ste…
A Vindication of the RR Lyrae Fourier Light Curve Decomposition for the Calculation of Metallicity and Distance in Globular Clusters
Arellano Ferro, A.
We report the mean metallicity and absolute magnitude of RR Lyrae stars in a sample of 37 globular clusters, calculated via the Fourier decomposition of their light curves and ad hoc semi-empirical calibrations, in an unprecedented homogeneous approach. This enabled a new discussion of the metallicity dependence of the horizontal branch (HB) lumin…
A White Dwarf-Main-sequence Binary Unveiled by Time-domain Observations from LAMOST and TESS
Liu, Jifeng; Zong, Weikai; Bai, Yu +16 more
We report a single-lined white dwarf-main-sequence binary system, LAMOST J172900.17+652952.8, which is discovered by the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST)'s medium-resolution time-domain surveys. The radial-velocity semi-amplitude and orbital period of the optical visible star are measured by using follow-up observ…