Search Publications
Understanding SDO/AIA Observations of the 2010 June 13 EUV Wave Event: Direct Insight from a Global Thermodynamic MHD Simulation
Lugaz, Noé; Downs, Cooper; Roussev, Ilia I. +2 more
In this work, we present a comprehensive observation and modeling analysis of the 2010 June 13 extreme-ultraviolet (EUV) wave observed by the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO). Due to extreme advances in cadence, resolution, and bandpass coverage in the EUV regime, the AIA instrument offers an unprecede…
High-velocity clouds as streams of ionized and neutral gas in the halo of the Milky Way
Lehner, N.; Fox, A. J.; Tripp, T. M. +4 more
High-velocity clouds (HVCs), fast-moving ionized and neutral gas clouds found at high galactic latitudes, may play an important role in the evolution of the Milky Way. The extent of this role depends sensitively on their distances and total sky covering factor. We search for HVC absorption in Hubble Space Telescope high-resolution ultraviolet (UV)…
Measurement of Galactic Logarithmic Spiral Arm Pitch Angle Using Two-dimensional Fast Fourier Transform Decomposition
Davis, Benjamin L.; Kennefick, Daniel; Kennefick, Julia +5 more
A logarithmic spiral is a prominent feature appearing in a majority of observed galaxies. This feature has long been associated with the traditional Hubble classification scheme, but historical quotes of pitch angle of spiral galaxies have been almost exclusively qualitative. We have developed a methodology, utilizing two-dimensional fast Fourier …
The blue UV slopes of z ~ 4 Lyman break galaxies: implications for the corrected star formation rate density
Maiolino, R.; Castellano, M.; Pentericci, L. +13 more
Context. Study of the dust extinction in high-redshift galaxies is fundamental to obtaining an estimate of the corrected star formation rate density (SFRD) and to put constraints on galaxy evolution models.
Aims: We plan to analyse dust extinction in Lyman break galaxies (LBGs) by introducing a new and more reliable approach to their selectio…
Inferences on the Distribution of Lyα Emission of z ~ 7 and z ~ 8 Galaxies
Stiavelli, Massimo; Treu, Tommaso; Trenti, Michele +2 more
Spectroscopic confirmation of galaxies at z ~ 7 and above has been extremely difficult, owing to a drop in intensity of Lyα emission in comparison with samples at z ~ 6. This crucial finding could potentially signal the ending of cosmic reionization. However, it is based on small data sets, often incomplete and heterogeneous in nature. We introduc…
The low-mass end of the fundamental relation for gravitationally lensed star-forming galaxies at 1 < z < 6
Richard, Johan; Hjorth, Jens; Grillo, Claudio +6 more
We present Very Large Telescope/X-shooter spectra of 13 galaxies in the redshift range 1 ≲ z ≲ 6, which are strongly lensed by massive galaxy clusters. Spectroscopic redshifts are measured for nine galaxies, while three sources have redshifts determined from continuum breaks in their spectra. The stellar masses of the galaxies span four orders of …
Reconstruction of total solar irradiance 1974-2009
Jaffe, A. H.; Krivova, N. A.; Solanki, S. +4 more
Context. The study of variations in total solar irradiance (TSI) is important for understanding how the Sun affects the Earth's climate.
Aims: Full-disk continuum images and magnetograms are now available for three full solar cycles. We investigate how modelled TSI compares with direct observations by building a consistent modelled TSI datase…
The Impact of Evolving Infrared Spectral Energy Distributions of Galaxies on Star Formation Rate Estimates
Berta, S.; Magnelli, B.; Nordon, R. +27 more
We combine Herschel-Photodetector Array Camera and Spectrometer (PACS) data from the PACS Evolutionary Probe (PEP) program with Spitzer 24 µm and 16 µm photometry and ultra deep Infrared Spectrograph (IRS) mid-infrared spectra to measure the mid- to far-infrared spectral energy distribution (SED) of 0.7 < z < 2.5 normal star-form…
Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library
Koleva, M.; Vazdekis, A.
Context. The spectral predictions of stellar population models are not as accurate in the ultra-violet (UV) as in the optical wavelength domain. One of the reasons is the lack of high-quality stellar libraries. The New Generation Stellar Library (NGSL), recently released, represents a significant step towards the improvement of this situation.
The Molecular Gas Content of z = 3 Lyman Break Galaxies: Evidence of a Non-evolving Gas Fraction in Main-sequence Galaxies at z > 2
Aussel, H.; Daddi, E.; Elbaz, D. +10 more
We present observations of the CO[J = 3 → 2] emission toward two massive and infrared luminous Lyman break galaxies (LBGs) at z = 3.21 and z = 2.92, using the IRAM Plateau de Bure Interferometer, placing first constraints on the molecular gas masses (M gas) of non-lensed LBGs. Their overall properties are consistent with those of typica…