Search Publications
OMEGA - OSIRIS Mapping of Emission-line Galaxies in A901/2 - II. Environmental influence on integrated star formation properties and AGN activity
Chies-Santos, Ana L.; Wolf, Christian; Aragón-Salamanca, Alfonso +6 more
We present a study of the star formation and AGN activity for galaxies in CP 15051 the Abell 901/2 multicluster system at z ∼ 0.167 as part of the OSIRIS Mapping of Emission-line Galaxies in A901/2 (OMEGA) survey. Using Tuneable Filter data obtained with the OSIRIS instrument at the Gran Telescopio Canarias, we produce spectra covering the Hα and …
Real-time prediction of the occurrence of GLE events
Núñez, Marlon; Reyes-Santiago, Pedro J.; Malandraki, Olga E.
A tool for predicting the occurrence of Ground Level Enhancement (GLE) events using the UMASEP scheme is presented. This real-time tool, called HESPERIA UMASEP-500, is based on the detection of the magnetic connection, along which protons arrive in the near-Earth environment, by estimating the lag correlation between the time derivatives of 1 min …
Potential cooling of an accretion-heated neutron star crust in the low-mass X-ray binary 1RXS J180408.9-342058
Altamirano, D.; Degenaar, N.; Wijnands, R. +11 more
We have monitored the transient neutron star low-mass X-ray binary 1RXS J180408.9-342058 in quiescence after its ∼4.5 month outburst in 2015. The source has been observed using Swift and XMM-Newton. Its X-ray spectra were dominated by a thermal component. The thermal evolution showed a gradual X-ray luminosity decay from ∼18 × 1032 to ∼…
North-south asymmetries in cold plasma density in the magnetotail lobes: Cluster observations
Snekvik, K.; Østgaard, N.; Tenfjord, P. +7 more
In this paper, we present observations of cold (0-70 eV) plasma density in the magnetotail lobes. The observations and results are based on 16 years of Cluster observation of spacecraft potential measurements converted into local plasma densities. Measurements from all four Cluster spacecraft have been used, and the survey indicates a persistent a…
SED-dependent galactic extinction prescription for Euclid and future cosmological surveys
Paltani, Stéphane; Galametz, Audrey; Saglia, Roberto +2 more
The outcome of upcoming cosmological surveys will depend on the accurate estimates of photometric redshifts. In the framework of the implementation of the photometric redshift algorithm for the ESA Euclid mission, we are exploring new avenues to improve current template-fitting methods. This paper focusses in particular on the prescription of the …
Galaxy Populations in Massive z = 0.2-0.9 Clusters. I. Analysis of Spectroscopy
Jørgensen, Inger; Chiboucas, Kristin; Takamiya, Marianne +3 more
We present an analysis of stellar populations in passive galaxies in seven massive X-ray clusters at z = 0.19-0.89. Based on absorption-line strengths measured from our high signal-to-noise spectra, the data support primarily passive evolution of the galaxies. We use the scaling relations between velocity dispersions and the absorption-line streng…
Magnetic Flux Rope Shredding By a Hyperbolic Flux Tube: The Detrimental Effects of Magnetic Topology on Solar Eruptions
Vourlidas, Angelos; Stenborg, Guillermo; Chintzoglou, Georgios +3 more
We present the analysis of an unusual failed eruption captured in high cadence and in many wavelengths during the observing campaign in support of the Very high Angular resolution Ultraviolet Telescope (VAULT2.0) sounding rocket launch. The refurbished VAULT2.0 is a Lyα (λ 1216 Å) spectroheliograph launched on 2014 September 30. The campaign targe…
A Universal Correlation between Star Formation Activity and Molecular Gas Properties Across Environments
Nakagawa, Takao; Suzuki, Tomoko L.; Koyama, Yusei +10 more
We present the molecular gas mass fraction ({f}{{{H}}2}) and star formation efficiency (SFE) of local galaxies on the basis of our new CO(J=1-0) observations with the Nobeyama 45 m radio telescope, combined with the COLDGASS galaxy catalog, as a function of galaxy environment defined as the local number density of galaxies me…
NuSTAR Hard X-Ray Observations of the Energetic Millisecond Pulsars PSR B1821-24, PSR B1937+21, and PSR J0218+4232
Gotthelf, E. V.; Bogdanov, S.
We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray timing and spectroscopy of the three exceptionally energetic rotation-powered millisecond pulsars PSRs B1821-24, B1937+21, and J0218+4232. By correcting for the frequency and phase drifts of the NuSTAR onboard clock, we are able to recover the intrinsic hard X-ray pulse profiles …
A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers
Wang, Chih-Ping; Liu, Terry Z.; Angelopoulos, Vassilis +9 more
We investigate a quiet time event of magnetospheric Pc5 ultralow-frequency (ULF) waves and their likely external drivers using multiple spacecraft observations. Enhancements of electric and magnetic field perturbations in two narrow frequency bands, 1.5-2 mHz and 3.5-4 mHz, were observed over a large radial distance range from r 5 to 11 RE