1,140 research outputs found
A First Amendment Right to Observe Elections: Fulfilling the Dream of \u3ci\u3eRichmond Newspapers\u3c/i\u3e by Extending It to the Polling Place
The First Amendment has long been held to protect the right of citizens to gather information. In 1980, the Supreme Court articulated a two-pronged test in Richmond Newspapers v. Virginia, which examined both the “experience” and “logic” of granting public access to criminal trials. The jurisprudence of lower courts has since extended this qualified First Amendment presumptive right of access to civil trial and administrative hearings. This Comment examines the extension of this constitutional test to the governmental process at work at polling places. This Comment argues that the public, via the powerful vehicle of the press, ultimately meets the “experience and logic” test and possesses a qualified First Amendment right of access to the polling place. Finally, this Comment notes that a constitutional presumption of access need not infringe upon the individual rights of voters
Predicted and observed evolution in the mean properties of Type Ia supernovae with redshift
Recent studies indicate that Type Ia supernovae (SNe Ia) consist of two
groups - a "prompt" component whose rates are proportional to the host galaxy
star formation rate, whose members have broader lightcurves and are
intrinsically more luminous, and a "delayed" component whose members take
several Gyr to explode, have narrower lightcurves, and are intrinsically
fainter. As cosmic star formation density increases with redshift, the prompt
component should begin to dominate. We use a two-component model to predict
that the average lightcurve width should increase by 6% from z=0-1.5. Using
data from various searches we find an 8.1% +/- 2.7% increase in average
lightcurve width for non-subluminous SNe Ia from z=0.03 - 1.12, corresponding
to an increase in the average intrinsic luminosity of 12%. To test whether
there is any bias after supernovae are corrected for lightcurve shape we use
published data to mimic the effect of population evolution and find no
significant difference in the measured dark energy equation of state parameter,
w. However, future measurements of time-variable w will require standardization
of SN Ia magnitudes to 2% up to z=1.7, and it is not yet possible to assess
whether lightcurve shape correction works at this level of precision. Another
concern at z=1.5 is the expected order of magnitude increase in the number of
SNe Ia that cannot be calibrated by current methods.Comment: 5 pages, 3 figures, accepted to ApJ Letters, addressed referee's
comments, table adde
Needle in a Haystack: Finding Supermassive Black Hole-Related Flares in the Zwicky Transient Facility Public Survey
Transient accretion events onto supermassive black holes (SMBHs), such as
tidal disruption events (TDEs), Bowen Fluorescence Flares (BFFs), and active
galactic nuclei (AGNs), which are accompanied by sudden increases of activity,
offer a new window onto the SMBH population, accretion physics, and stellar
dynamics in galaxy centers. However, such transients are rare and finding them
in wide-field transient surveys is challenging. Here we present the results of
a systematic real-time search for SMBH-related transients in Zwicky Transient
Facility (ZTF) public alerts, using various search queries. We examined 345
rising events coincident with a galaxy nucleus, with no history of previous
activity, of which 223 were spectroscopically classified. Of those, five (2.2%)
were TDEs, one (0.5%) was a BFF, and two (0.9%) were AGN flares. Limiting the
search to blue events, the fraction of TDEs nearly doubles to 4.1%, and no TDEs
are missed. Limiting the search further to candidate post-starburst galaxies
increases the relative number of TDEs to 16.7%, but the absolute numbers in
such a search are small. The main contamination source is supernovae (95.1% of
classified events), of which the majority (82.2% of supernovae) are of Type Ia.
In a comparison set of 39 events with limited photometric history, the AGN
contamination increases to ~30%. Host galaxy offset is not a significant
discriminant of TDEs in current ZTF data, but might be useful in
higher-resolution data. Our results can be used to quantify the efficiency of
various SMBH-related transient search strategies in optical surveys such as ZTF
and the Legacy Survey of Space and Time.Comment: Accepted to Ap
The Dynamic Universe: Realizing the Potential of Classical Time Domain and Multimessenger Astrophysics
In parallel with the multi-messenger revolution, major advances in time-domain astronomy across multiple science disciplines relevant to astrophysics are becoming more urgent to address. Aside from electromagnetic observations of gravitational wave events and explosive counterparts, there are a number of “classical” astrophysical areas that require new thinking for proper exploration in the time domain. How NASA, NSF, ESA, and ESO consider the 2020 USA Decadal Survey within the astronomy community, as well as the worldwide call to support and expand time domain and multi-messenger astrophysics, it is crucial that all areas of astrophysics, including stellar, galactic, Solar System, and exoplanetary science participate in the discussion, and that it not be made into an exclusive preserve of cosmological, high-energy, explosive and transient science. Time domain astronomy is used to explore many aspects of astrophysics–particularly concerning ground- and space-based mission science goals of exploring how the Universe works, understanding how did we get here, and are we alone. Time domain studies are already built into the core operations of many currently operating and future space telescopes (e.g., Roman, PLATO) as well as current and planned large areal ground-based surveys (e.g., Rubin). Time-domain observations designed for one scientific purpose, also lead to great discoveries in many other science areas. The recent advent of user-friendly hardware, software, observational approaches, and online data infrastructure has also helped make time domain observations especially suitable and appealing for citizen science projects. We provide a review of the current state of TDAMM alerts and observational protocols, revealing a wide array of software and applications, much of which is incompatible. Any conversation regarding TDAMM astrophysics should include all aspects of the field, including those aspects seen as classical applications
Atlantis Program allows EU, US students to focus on biorenewable resources
EU-US Atlantis is an umbrella program for a variety of inno vative educational opportunities for students and faculty to study and conduct research abroad and for curriculum development. The Integral Valorization of Bio-Production (IVBP) program, funded for 2008-2012, provides financial assistance for US students to study in Europe and for EU students to study in the United States
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