94 research outputs found
The Brownian Web: Characterization and Convergence
The Brownian Web (BW) is the random network formally consisting of the paths
of coalescing one-dimensional Brownian motions starting from every space-time
point in . We extend the earlier work of Arratia
and of T\'oth and Werner by providing characterization and convergence results
for the BW distribution, including convergence of the system of all coalescing
random walkssktop/brownian web/finale/arXiv submits/bweb.tex to the BW under
diffusive space-time scaling. We also provide characterization and convergence
results for the Double Brownian Web, which combines the BW with its dual
process of coalescing Brownian motions moving backwards in time, with forward
and backward paths ``reflecting'' off each other. For the BW, deterministic
space-time points are almost surely of ``type'' -- {\em zero} paths
into the point from the past and exactly {\em one} path out of the point to the
future; we determine the Hausdorff dimension for all types that actually occur:
dimension 2 for type , 3/2 for and , 1 for , and 0
for and .Comment: 52 pages with 4 figure
1D Aging
We derive exact expressions for a number of aging functions that are scaling
limits of non-equilibrium correlations, R(tw,tw+t) as tw --> infinity with t/tw
--> theta, in the 1D homogenous q-state Potts model for all q with T=0 dynamics
following a quench from infinite temperature. One such quantity is (the
two-point, two-time correlation function) when
n/sqrt(tw) --> z. Exact, closed-form expressions are also obtained when one or
more interludes of infinite temperature dynamics occur. Our derivations express
the scaling limit via coalescing Brownian paths and a ``Brownian space-time
spanning tree,'' which also yields other aging functions, such as the
persistence probability of no spin flip at 0 between tw and tw+t.Comment: 4 pages (RevTeX); 2 figures; submitted to Physical Review Letter
Does consultation improve decision-making?
This paper reports an experiment designed to test whether prior consultation within a group affects subsequent individual decision-making in tasks where demonstrability of correct solutions is low. In our experiment, subjects considered two paintings created by two different artists and were asked to guess which artist made each painting. We observed answers given by individuals under two treatments: In one, subjects were allowed the opportunity to consult with other participants before making their private decisions; in the other, there was no such opportunity. Our primary findings are that subjects in the first treatment evaluate the opportunity to consult positively, but they perform significantly worse and earn significantly less
Vaccine-Induced Immunity in Baboons by Using DNA and Replication-Incompetent Adenovirus Type 5 Vectors Expressing a Human Immunodeficiency Virus Type 1 gag Gene
This is the published version. Copyright 2003 American Society for Microbiology.The cellular immunogenicity of formulated plasmid DNA and replication-defective human adenovirus serotype 5 (Ad5) vaccine vectors expressing a codon-optimized human immunodeficiency virus type 1 gag gene was examined in baboons. The Ad5 vaccine was capable of inducing consistently strong, long-lived CD8+-biased T-cell responses and in vitro cytotoxic activities. The DNA vaccine-elicited immune responses were weaker than those elicited by the Ad5 vaccine and highly variable; formulation with chemical adjuvants led to moderate increases in the levels of Gag-specific T cells. Increasing the DNA-primed responses with booster doses of either Ad5 or modified vaccinia virus Ankara vaccines suggests a difference in the relative levels of cytotoxic and helper responses. The implications of these results are discussed
Observing galaxy clusters and the cosmic web through the Sunyaev Zel'dovich effect with MISTRAL
Galaxy clusters and surrounding medium, can be studied using X-ray
bremsstrahlung emission and Sunyaev Zel'dovich (SZ) effect. Both astrophysical
probes, sample the same environment with different parameters dependance. The
SZ effect is relatively more sensitive in low density environments and thus is
useful to study the filamentary structures of the cosmic web. In addition,
observations of the matter distribution require high angular resolution in
order to be able to map the matter distribution within and around galaxy
clusters. MISTRAL is a camera working at 90GHz which, once coupled to the
Sardinia Radio Telescope, can reach angular resolution over field
of view (f.o.v.). The forecasted sensitivity is
and the mapping speed is . MISTRAL was recently
installed at the focus of the SRT and soon will take its first photons.Comment: To appear in Proc. of the mm Universe 2023 conference, Grenoble
(France), June 2023, published by F. Mayet et al. (Eds), EPJ Web of
conferences, EDP Science
TOI 122b And TOI 237b: Two Small Warm Planets Orbiting Inactive M Dwarfs Found By TESS
We report the discovery and validation of TOI 122b and TOI 237b, two warm planets transiting inactive M dwarfs observed by the Transiting Exoplanet Survey Satellite (TESS). Our analysis shows that TOI 122b has a radius of 2.72 ± 0.18 R⊕ and receives 8.8 ± 1.0 times Earth\u27s bolometric insolation, and TOI 237b has a radius of 1.44±0.12 R⊕ and receives 3.7 ± 0.5 times Earth\u27s insolation, straddling the 6.7 × Earth insolation that Mercury receives from the Sun. This makes these two of the cooler planets yet discovered by TESS, even on their 5.08 and 5.43 day orbits. Together, they span the small-planet radius valley, providing useful laboratories for exploring volatile evolution around M dwarfs. Their relatively nearby distances (62.23 ± 0.21 pc and 38.11 ± 0.23 pc, respectively) make them potentially feasible targets for future radial velocity follow-up and atmospheric characterization, although such observations may require substantial investments of time on large telescopes
Two super-Earths at the edge of the habitable zone of the nearby M dwarf TOI-2095
The main scientific goal of TESS is to find planets smaller than Neptune
around stars bright enough to allow further characterization studies. Given our
current instrumentation and detection biases, M dwarfs are prime targets to
search for small planets that are in (or nearby) the habitable zone of their
host star. Here we use photometric observations and CARMENES radial velocity
measurements to validate a pair of transiting planet candidates found by TESS.
The data was fitted simultaneously using a Bayesian MCMC procedure taking into
account the stellar variability present in the photometric and spectroscopic
time series. We confirm the planetary origin of the two transiting candidates
orbiting around TOI-2095 (TIC 235678745). The star is a nearby M dwarf ( pc, K, mag) with a
stellar mass and radius of and , respectively. The planetary system is composed of
two transiting planets: TOI-2095b with an orbital period of days and TOI-2095c with days. Both planets have similar sizes with and for planet b and c,
respectively. We put upper limits on the masses of these objects with for the inner and for the outer planet
(95\% confidence level). These two planets present equilibrium temperatures in
the range of 300 - 350 K and are close to the inner edge of the habitable zone
of their star.Comment: Submitted to Astronomy & Astrophysic
Two Warm Super-Earths Transiting the Nearby M Dwarf TOI-2095
We report the detection and validation of two planets orbiting TOI-2095 (TIC
235678745). The host star is a 3700K M1V dwarf with a high proper motion. The
star lies at a distance of 42 pc in a sparsely populated portion of the sky and
is bright in the infrared (K=9). With data from 24 Sectors of observation
during TESS's Cycles 2 and 4, TOI-2095 exhibits two sets of transits associated
with super-Earth-sized planets. The planets have orbital periods of 17.7 days
and 28.2 days and radii of 1.30 and 1.39 Earth radii, respectively. Archival
data, preliminary follow-up observations, and vetting analyses support the
planetary interpretation of the detected transit signals. The pair of planets
have estimated equilibrium temperatures of approximately 400 K, with stellar
insolations of 3.23 and 1.73 times that of Earth, placing them in the Venus
zone. The planets also lie in a radius regime signaling the transition between
rock-dominated and volatile-rich compositions. They are thus prime targets for
follow-up mass measurements to better understand the properties of warm,
transition radius planets. The relatively long orbital periods of these two
planets provide crucial data that can help shed light on the processes that
shape the composition of small planets orbiting M dwarfs.Comment: Submitted to AAS Journal
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