Search Publications

Diffusion in unimodular gravity: Analytical solutions, late-time acceleration, and cosmological constraints
DOI: 10.1103/PhysRevD.102.023508 Bibcode: 2020PhRvD.102b3508C

Corral, Cristóbal; Cruz, Norman; González, Esteban

Unimodular gravity is an appealing approach to address the cosmological constant problem. In this scenario, the vacuum energy density of quantum fields does not gravitate and the cosmological constant appears merely as an integration constant. Recently, it has been shown that energy diffusion that may arise in quantum gravity and in theories with …

2020 Physical Review D
eHST 22
The Drivers of Active Region Outflows into the Slow Solar Wind
DOI: 10.3847/1538-4357/ab8a4c Bibcode: 2020ApJ...894..144B

Golub, Leon; Winebarger, Amy R.; Warren, Harry P. +13 more

Plasma outflows from the edges of active regions have been suggested as a possible source of the slow solar wind. Spectroscopic measurements show that these outflows have an enhanced elemental composition, which is a distinct signature of the slow wind. Current spectroscopic observations, however, do not have sufficient spatial resolution to disti…

2020 The Astrophysical Journal
Hinode 22
The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. I. Survey Overview and First Results for Andromeda I
DOI: 10.3847/1538-4357/ab88a2 Bibcode: 2020ApJ...894..135S

Javadi, Atefeh; Saremi, Elham; van Loon, Jacco Th. +10 more

An optical monitoring survey in nearby dwarf galaxies was carried out with the 2.5 m Isaac Newton Telescope. Fifty-five dwarf galaxies and four isolated globular clusters in the Local Group were observed with the Wide Field Camera. The main aims of this survey are to identify the most evolved asymptotic giant branch (AGB) stars and red supergiants…

2020 The Astrophysical Journal
Gaia 21
Trans-iron Ge, As, Se, and heavier elements in the dwarf metal-poor stars HD 19445, HD 84937, HD 94028, HD 140283, and HD 160617
DOI: 10.1051/0004-6361/202037689 Bibcode: 2020A&A...638A..64P

Spite, M.; Barbuy, B.; Peterson, R. C.

Context. The spectra of unevolved metal-poor halo stars uniquely reflect the elemental abundances incorporated during the earliest Galactic epoch. Their heavy-element content is well understood as the products of neutron capture on iron-peak elements. However, for the lightest trans-iron elements with atomic number 30 < Z < 52, they show str…

2020 Astronomy and Astrophysics
eHST 21
A Chemo-dynamical Link between the Gjöll Stream and NGC 3201
DOI: 10.3847/1538-4357/ababa5 Bibcode: 2020ApJ...901...23H

Marshall, J. L.; Sneden, C.; Hansen, T. T. +4 more

Recent analysis of the second data release of Gaia has revealed a number of new stellar streams surrounding the Milky Way. It has been suggested that one of these streams, Gjöll, is associated with the globular cluster NGC 3201, but thus far the association has only been based on kinematics of the stream stars. In this work we identify five likely…

2020 The Astrophysical Journal
Gaia 21
GalWeight Application: A Publicly Available Catalog of Dynamical Parameters of 1800 Galaxy Clusters from SDSS-DR13, (GalWCat19)
DOI: 10.3847/1538-4365/ab536e Bibcode: 2020ApJS..246....2A

Old, Lyndsay; Wilson, Gillian; Abdullah, Mohamed H. +3 more

Utilizing the SDSS-DR13 spectroscopic data set, we create a new publicly available catalog of 1800 galaxy clusters (GalWeight cluster catalog, GalWCat19) and a corresponding catalog of 34,471 identified member galaxies. The clusters are identified from overdensities in redshift phase space. The GalWeight technique introduced by Abdullah et al. is …

2020 The Astrophysical Journal Supplement Series
eHST 21
The CARMENES search for exoplanets around M dwarfs. Dynamical characterization of the multiple planet system GJ 1148 and prospects of habitable exomoons around GJ 1148 b
DOI: 10.1051/0004-6361/201936987 Bibcode: 2020A&A...638A..16T

Schmitt, J. H. M. M.; Amado, P. J.; Bauer, F. F. +29 more

Context. GJ 1148 is an M-dwarf star hosting a planetary system composed of two Saturn-mass planets in eccentric orbits with periods of 41.38 and 532.02 days.
Aims: We reanalyze the orbital configuration and dynamics of the GJ 1148 multi-planetary system based on new precise radial velocity measurements taken with CARMENES.
Methods: We co…

2020 Astronomy and Astrophysics
Gaia 21
The kinematical and space structures of IC 2391 open cluster and moving group with Gaia-DR2
DOI: 10.1088/1674-4527/20/2/16 Bibcode: 2020RAA....20...16P

Vereshchagin, S. V.; Chupina, N. V.; Postnikova, E. S. +3 more

The kinematical parameters, spatial shape and structure of the open cluster IC 2391 and the associated stellar stream are studied here using Gaia Data Release 2 (GDR2) astrometry data. The apex positions are determined for the open cluster IC 2391 (data taken from Cantat-Gaudin et al.) and for the kinematical stream's stars mentioned in Montes et …

2020 Research in Astronomy and Astrophysics
Gaia 21
Low-level Carbon Monoxide Line Polarization in Two Protoplanetary Disks: HD 142527 and IM Lup
DOI: 10.3847/1538-4357/abaef7 Bibcode: 2020ApJ...901...71S

Li, Zhi-Yun; Teague, Richard; Looney, Leslie W. +2 more

Magnetic fields are expected to play an important role in accretion processes for circumstellar disks. However, measuring the magnetic field morphology is difficult, especially when given that polarimetric (sub)millimeter continuum observations may not trace the fields in most disks. The Goldreich-Kylafis effect suggests that line polarization is …

2020 The Astrophysical Journal
Gaia 21
Plasma Wave Investigation (PWI) Aboard BepiColombo Mio on the Trip to the First Measurement of Electric Fields, Electromagnetic Waves, and Radio Waves Around Mercury
DOI: 10.1007/s11214-020-00692-9 Bibcode: 2020SSRv..216...65K

Karlsson, Tomas; Moncuquet, Michel; Issautier, Karine +14 more

The Plasma Wave Investigation (PWI) aboard the BepiColombo Mio (Mercury Magnetospheric Orbiter, MMO) will enable the first observations of electric fields, plasma waves, and radio waves in and around the Hermean magnetosphere and exosphere. The PWI has two sets of receivers (EWO with AM2P, SORBET) connected to two electric field sensors…

2020 Space Science Reviews
BepiColombo 21