Search Publications
Characteristics and Energy Dependence of Recurrent Galactic Cosmic-Ray Flux Depressions and of a Forbush Decrease with LISA Pathfinder
Mendes, L.; Russano, G.; Lloro, I. +82 more
Galactic cosmic-ray (GCR) energy spectra observed in the inner heliosphere are modulated by the solar activity, the solar polarity and structures of solar and interplanetary origin. A high counting rate particle detector (PD) aboard LISA Pathfinder, meant for subsystems diagnostics, was devoted to the measurement of GCR and solar energetic particl…
A Multiwavelength View of the Neutron Star Binary 1FGL J1417.7-4402: A Progenitor to Canonical Millisecond Pulsars
Strader, Jay; Bahramian, Arash; Cheung, C. C. +6 more
The Fermi γ-ray source 1FGL J1417.7-4407 (J1417) is a compact X-ray binary with a neutron star primary and a red giant companion in a ∼5.4 days orbit. This initial conclusion, based on optical and X-ray data, was confirmed when a 2.66 ms radio pulsar was found at the same location (and with the same orbital properties) as the optical/X-ray source.…
Deciphering the Activity and Quiescence of High-redshift Cluster Environments: ALMA Observations of Cl J1449+0856 at z = 2
Finoguenov, A.; Cimatti, A.; Daddi, E. +13 more
We present Atacama Large Millimeter/submillimeter Array observations of the 870 µm continuum and CO(4-3) line emission in the core of the galaxy cluster Cl J1449+0856 at z = 2, a near-IR-selected, X-ray-detected system in the mass range of typical progenitors of today’s massive clusters. The 870 µm map reveals six F 870µm
Two-phase Heating in Flaring Loops
Qiu, Jiong; Longcope, Dana W.; Zhu, Chunming
We analyze and model a C5.7 two-ribbon solar flare observed by the Solar Dynamics Observatory, Hinode, and GOES on 2011 December 26. The flare is made of many loops formed and heated successively over one and half hours, and their footpoints are brightened in the UV 1600 Å before enhanced soft X-ray and EUV missions are observed in flare loops. As…
A Data-constrained Model for Coronal Mass Ejections Using the Graduated Cylindrical Shell Method
Singh, T.; Yalim, M. S.; Pogorelov, N. V.
Coronal mass ejections (CMEs) are major drivers of extreme space weather conditions, as this is a matter of serious concern for our modern technologically dependent society. The development of numerical approaches that would simulate CME generation and propagation through the interplanetary space is an important step toward our capability to predi…
Far-UV HST Spectroscopy of an Unusual Hydrogen-poor Superluminous Supernova: SN2017egm
Brown, P. J.; Quimby, R.; Lunnan, R. +4 more
SN2017egm is the closest (z = 0.03) H-poor superluminous supernova (SLSN-I) detected to date, and a rare example of an SLSN-I in a massive, metal-rich galaxy. We present the HST UV and optical spectra covering 1000-5500 Å, taken at +3 day relative to the peak. Our data reveal two absorption systems at redshifts matching the host galaxy NGC 3191 (z…
Progenitor Mass Distribution for Core-collapse Supernova Remnants in M31 and M33
Dolphin, Andrew E.; Williams, Benjamin F.; Dalcanton, Julianne J. +3 more
Using the star formation histories (SFHs) near 94 supernova remnants (SNRs), we infer the progenitor mass distribution for core-collapse supernovae. We use Bayesian inference and model each SFH with multiple bursts of star formation (SF), one of which is assumed to be associated with the SNR. Assuming single-star evolution, the minimum mass of CCS…
Upper Limits on the Presence of Central Massive Black Holes in Two Ultra-compact Dwarf Galaxies in Centaurus A
Romanowsky, Aaron J.; Neumayer, Nadine; Strader, Jay +10 more
The recent discovery of massive black holes (BHs) in the centers of high-mass ultra-compact dwarf galaxies (UCDs) suggests that at least some are the stripped nuclear star clusters of dwarf galaxies. We present the first study that investigates whether such massive BHs, and therefore stripped nuclei, also exist in low-mass (M < 107 M…
The Rest-frame Optical Sizes of Massive Galaxies with Suppressed Star Formation at z ∼ 4
Toft, Sune; Kubo, Mariko; Tanaka, Masayuki +3 more
We present the rest-frame optical sizes of massive quiescent galaxies (QGs) at z ∼ 4 measured at the K‧-band with the Infrared Camera and Spectrograph and adaptive optics (AO) facility, AO188, on the Subaru telescope. Based on a deep multiwavelength catalog in the Subaru XMM-Newton Deep Survey Field, covering a wide wavelength range from the u-ban…
Hubble Space Telescope Wide Field Camera 3 Observations of Escaping Lyman Continuum Radiation from Galaxies and Weak AGN at Redshifts z ∼ 2.3-4.1
Koekemoer, Anton M.; Inoue, Akio K.; Jiang, Linhua +9 more
We present observations of escaping Lyman Continuum (LyC) radiation from 34 massive star-forming galaxies (SFGs) and 12 weak AGN with reliably measured spectroscopic redshifts at z≃ 2.3{--}4.1. We analyzed Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) mosaics of the Early Release Science (ERS) field in three UVIS filters to sample the re…