Search Publications
Messier 81's Planck view versus its halo mapping
Nucita, A. A.; De Paolis, F.; Ingrosso, G. +8 more
This paper is a follow-up of a previous paper about the M 82 galaxy and its halo based on Planck observations. As in the case of M 82, a substantial north-south and east-west temperature asymmetry is also found for the M 81 galaxy, extending up to galactocentric distances of about 1.5°. The temperature asymmetry is almost frequency independent and…
Chemo-kinematic Ages of Eccentric-planet-hosting M Dwarf Stars
Muirhead, Philip S.; Veyette, Mark J.
The M dwarf stars are exciting targets for exoplanet investigations; however, their fundamental stellar properties are difficult to measure. Perhaps the most challenging property is stellar age. Once on the main sequence, M dwarfs change imperceptibly in their temperature and luminosity, necessitating novel statistical techniques for estimating th…
Solar chemical composition in the hot gas of cool-core ellipticals, groups, and clusters of galaxies
Urdampilleta, I.; Simionescu, A.; Kaastra, J. S. +6 more
The hot intracluster medium (ICM) pervading galaxy clusters and groups is rich in metals, which were synthesized by billions of supernovae and have accumulated in cluster gravitational wells for several gigayears. Since the products of both Type Ia and core-collapse supernovae - expected to explode over different time-scales - are found in the ICM…
Photospheric and Coronal Abundances in an X8.3 Class Limb Flare
Culhane, J. L.; Doschek, G. A.; Warren, H. P. +3 more
We analyze solar elemental abundances in coronal post-flare loops of an X8.3 flare (SOL2017-09-10T16:06) observed on the west limb on 2017 September 10 near 18 UT using spectra recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. The abundances in the corona can differ from photospheric abundances due to the fir…
Small-Scale Flux Transfer Events Formed in the Reconnection Exhaust Region Between Two X Lines
Russell, C. T.; Eastwood, J. P.; Lavraud, B. +18 more
We report MMS observations of the ion-scale flux transfer events (FTEs) that may involve two main X lines and tearing instability between the two X lines. The four spacecraft detected multiple isolated regions with enhanced magnetic field strength and bipolar Bn signatures normal to the nominal magnetopause, indicating FTEs. The current…
Contrasting dynamics of electrons and protons in the near-Earth plasma sheet during dipolarization
Grigorenko, Elena E.; Kronberg, Elena A.; Daly, Patrick W. +4 more
The fortunate location of Cluster and the THEMIS P3 probe in the near-Earth plasma sheet (PS) (at X ∼ -7-9 RE) allowed for the multipoint analysis of properties and spectra of electron and proton injections. The injections were observed during dipolarization and substorm current wedge formation associated with braking of multiple bursty…
Bipolar H II regions. II. Morphologies and star formation in their vicinities
Zavagno, A.; Samal, M. R.; Molinari, S. +3 more
Aims: We aim to identify bipolar Galactic H II regions and to understand their parental cloud structures, morphologies, evolution, and impact on the formation of new generations of stars.
Methods: We use the Spitzer-GLIMPSE, Spitzer-MIPSGAL, and Herschel-Hi-GAL surveys to identify bipolar H II regions and to examine their morphologies. W…
Cepheids in M31: The PAndromeda Cepheid Sample
Lee, Chien-Hsiu; Bender, Ralf; Seitz, Stella +15 more
We present the largest Cepheid sample in M31 based on the complete Pan-STARRS1 survey of Andromeda (PAndromeda) in the r P1, i P1, and g P1 bands. We find 2686 Cepheids with 1662 fundamental-mode Cepheids, 307 first-overtone Cepheids, 278 type II Cepheids, and 439 Cepheids with undetermined Cepheid type. Using the …
The role of spiral arms in Milky Way star formation
Moore, T. J. T.; Elia, D.; Molinari, S. +4 more
What role does Galactic structure play in star formation? We have used the Herschel Infrared Galactic Plane Survey (Hi-GAL) compact-clump catalogue to examine trends in evolutionary stage over large spatial scales in the inner Galaxy. We examine the relationship between the fraction of clumps with embedded star formation (the star-forming fraction…
A Lyman limit system associated with galactic winds
Bouché, Nicolas; Pettini, Max; York, Donald G. +9 more
Projected quasar galaxy pairs provide powerful means to study the circumgalactic medium (CGM) that maintains the relics of galactic feedback and the accreted gas from the intergalactic medium. Here, we study the nature of a Lyman Limit system (LLS) with N(H I) = 1019.1 ± 0.3 cm-2 and a dust-uncorrected metallicity of [Fe/H] =…