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Swift/XRT Deep Galactic Plane Survey Discovery of a New Intermediate Polar Cataclysmic Variable, Swift J183920.1-045350
Göğüş, Ersin; Buckley, David; Kouveliotou, Chryssa +20 more
We report on the Swift/XRT Deep Galactic Plane Survey discovery and multiwavelength follow-up observations of a new intermediate polar (IP) cataclysmic variable, Swift J183920.1-045350. A 449.7 s spin period is found in XMM-Newton and NuSTAR data, accompanied by a 459.9 s optical period that is most likely the synodic, or beat period, produced fro…
Nearly 30,000 Late-type Main-sequence Stars with Stellar Age from LAMOST DR5
Zhao, Gang; Zhao, Jingkun; Ye, Xianhao +3 more
We construct a sample of nearly 30,000 main-sequence stars with 4500 K < Teff < 5000 K and stellar ages estimated by the chromospheric activity-age relation. This sample is used to determine the age distribution in the R-Z plane of the Galaxy, where R is the projected Galactocentric distance in the disk midplane and Z is the heigh…
RR Lyrae Stars in Stellar Streams with Gaia: The Escapers
Grebel, Eva K.; Simunovic, Mirko; Abbas, Mohamad
We attempt to identify RR Lyrae (RRL) stars in stellar streams that might have escaped from seven globular clusters (GCs) based on proper motions, distances, color-magnitude diagrams, and other properties extracted from the Gaia Early Data Release 3 (EDR3) database. Specifically, we cross-match two large RRL stars catalogs (from Gaia DR2 and Catal…
Variations of Peak He/H Ratios in Solar Energetic (E > 4 MeV) Particle Events and Comparisons with Solar Wind He/H Ratios
Brown, D.; Kahler, S. W.
We determine solar energetic particle (SEP) event He/H peak intensity ratios AHe observed in the four energy channels of the SOHO EPHIN detector covering 4-53 MeV nuc-1. Those SEP AHe values range over two orders of magnitude for 43 large western hemisphere SEP events through the period 1997-2017. AHe of…
Fe XII and Fe XIII Line Widths in the Polar Off-limb Solar Corona up to 1.5 R⊙
Landi, Enrico; Zhu, Yingjie; Szente, Judit
The nonthermal broadening of spectral lines formed in the solar corona is often used to seek evidence of Alfvén waves propagating in the corona. To have a better understanding of the variation of line widths at different altitudes, we measured the line widths of the strong Fe XII 192.4, 193.5, and 195.1 Å and Fe XIII 202.0 Å in an off-limb souther…
A Multi-wavelength Analysis of Small-scale Brightenings Observed by IRIS
Morgan, Huw; Humphries, Llŷr Dafydd
Small-scale brightenings in solar atmospheric observations are a manifestation of heating and/or energy transport events. We present statistical characteristics of brightenings from a new detection method applied to 1330, 1400, and 2796 Å IRIS slit-jaw image time series. A total of 2377 events were recorded that coexist in all three channels, givi…
Discovery of a Highly Collimated Flow from the High-mass Protostar ISOSS J23053+5953 SMM2
Zhang, Qizhou; Carrasco-González, Carlos; Linz, Hendrik +6 more
We present Very Large Array C-, X-, and Q-band continuum observations, as well as 1.3 mm continuum and CO(2-1) observations with the Submillimeter Array toward the high-mass protostellar candidate ISOSS J23053+5953 SMM2. Compact centimeter continuum emission was detected near the center of the SMM2 core with a spectral index of 0.24(± 0.15) betwee…
ALMA View of the ρ Ophiuchi A PDR with a 360 au Beam: The [C I] Emission Originates from the Plane-parallel PDR and Extended Gas
Nakamura, Fumitaka; Shimajiri, Yoshito; Yamagishi, Mitsuyoshi +5 more
We present the results of data analysis of the [C I] (3P1-3P0) emission from the ρ Ophiuchi A photon-dominated region (PDR) obtained in the ALMA ACA standalone mode with a spatial resolution of 2.6 arcsec (360 au). The [C I] emission shows filamentary structures with a width of ∼1000 au, which are adjace…
Do MURaM and STAGGER Simulations of Solar Faculae Match Observational Signatures from Magnetic Structures?
Cubas Armas, Melania; Fabbian, Damian
We compare results of simulations of solar facular-like conditions performed using the numerical codes MURaM and STAGGER. Both simulation sets have a similar setup, including the initial condition of ≈200 G vertical magnetic flux. After interpolating the output physical quantities to constant optical depth, we compare them and test them against in…
X-Ray Sources in the 1.75 Ms Ultra Narrow Deep Field Observed by XMM-Newton
Vignali, C.; Nicastro, F.; Krongold, Y. +5 more
In this work, we present the results of the survey carried out on one of the deepest X-ray fields observed by the XMM-Newton satellite. The 1.75 Ms Ultra Narrow Deep Field (XMM175UNDF) survey is made by 13 observations taken over 2 yr with a total exposure time of 1.75 Ms (1.372 Ms after flare-filtered) in a field of 30' × 30' centered around the …