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Big Data Assurance Evaluation: An SLA-Based Approach.
The Big Data community has started noticing that there is the need to complete Big Data platforms with assurance techniques proving the correct behavior of Big Data
analytics and management. In this paper, we propose a Big Data assurance solution based on Service-Level Agreements (SLAs), focusing on a platform providing Model-based Big Data Analytics-as-a-Service (MBDAaaS)
Solar particle effects on minor components of the Polar atmosphere
Abstract. Solar activity can influence the Earth's environment, and in particular the ozone layer, by direct modulation of the e.m. radiation or through variability of the incoming cosmic ray flux (solar and galactic particles). In particular, solar energetic particles (SEPs) provide additional external energy to the terrestrial environment; they are able to interact with the minor constituents of the atmospheric layer and produce ionizations, dissociations, dissociative ionizations and excitations. This paper highlights the SEP effects on the chemistry of the upper atmosphere by analysing some SEP events recorded during 2005 in the descending phase of the current solar cycle. It is shown that these events can lead to short- (hours) and medium- (days) term ozone variations through catalytic cycles (e.g. HOx and NOx increases). We focus attention on the relationship between ozone and OH data (retrieved from MLS EOS AURA) for four SEP events: 17 and 20 January, 15 May and 8 September. We confirm that SEP effects are different on the night and day hemispheres at high latitudes.</p
A new eclipsing binary system with a pulsating component detected by CoRoT
We report the discovery of CoRoT 102980178 (R.A.= 06:50:12.10, Dec.=
-02:41:21.8, J2000) an Algol-type eclipsing binary system with a pulsating
component (oEA). It was identified using a publicly available 55 day long
monochromatic lightcurve from the CoRoT initial run dataset (exoplanet field).
Eleven consecutive 1.26m deep total primary and the equal number of 0.25m deep
secondary eclipses (at phase 0.50) were observed. The following light elements
for the primary eclipse were derived: HJD_MinI= 2454139.0680 + 5.0548d x E. The
lightcurve modeling leads to a semidetached configuration with the photometric
mass ratio q=0.2 and orbital inclination i=85 deg. The out-of-eclipse
lightcurve shows ellipsoidal variability and positive O'Connell effect as well
as clear 0.01m pulsations with the dominating frequency of 2.75 c/d. The
pulsations disappear during the primary eclipses, which indicates the primary
(more massive) component to be the pulsating star. Careful frequency analysis
reveals the second independent pulsation frequency of 0.21 c/d and numerous
combinations of these frequencies with the binary orbital frequency and its
harmonics. On the basis of the CoRoT lightcurve and ground based multicolor
photometry, we favor classification of the pulsating component as a gamma
Doradus type variable, however, classification as an SPB star cannot be
excluded.Comment: 16 pages, 7 figures, 3 tables, accepted to Communications in
Asteroseismolog
SOPHIE velocimetry of Kepler transit candidates VI. An additional companion in the KOI-13 system
We report the discovery of a new stellar companion in the KOI-13 system.
KOI-13 is composed by two fast-rotating A-type stars of similar magnitude. One
of these two stars hosts a transiting planet discovered by Kepler. We obtained
new radial velocity measurements using the SOPHIE spectrograph at the
Observatoire de Haute-Provence that revealed an additional companion in this
system. This companion has a mass between 0.4 and 1 Msun and orbits one of the
two main stars with a period of 65.831 \pm 0.029 days and an eccentricity of
0.52 \pm 0.02. The radial velocities of the two stars were derived using a
model of two fast-rotating line profiles. From the residuals, we found a hint
of the stellar variations seen in the Kepler light curve with an amplitude of
about 1.41 km/s and a period close to the rotational period. This signal
appears to be about three order of magnitude larger than expected for stellar
activity. From the analysis of the residuals, we also put a 3-sigma upper-limit
on the mass of the transiting planet KOI-13.01 of 14.8 Mjup and 9.4 Mjup,
depending on which star hosts the transit. We found that this new companion has
no significant impact on the photometric determination of the mass of KOI-13.01
but is expected to affect precise infrared photometry. Finally, using dynamical
simulations, we infer that the new companion is orbiting around KOI-13B while
the transiting planet candidate is expected to orbit KOI-13A. Thus, the
transiting planet candidate KOI-13.01 is orbiting the main component of a
hierarchical triple system.Comment: Accepted in A&A Letters. 4 pages including 4 figures and the RV tabl
SOPHIE velocimetry of Kepler transit candidates XI. Kepler-412 system: probing the properties of a new inflated hot Jupiter
We confirm the planetary nature of Kepler-412b, listed as planet candidate
KOI-202 in the Kepler catalog, thanks to our radial velocity follow-up program
of Kepler-released planet candidates, which is on going with the SOPHIE
spectrograph. We performed a complete analysis of the system by combining the
Kepler observations from Q1 to Q15, to ground-based spectroscopic observations
that allowed us to derive radial velocity measurements, together with the host
star parameters and properties. We also analyzed the light curve to derive the
star's rotation period and the phase function of the planet, including the
secondary eclipse. We found the planet has a mass of 0.939 0.085
M and a radius of 1.325 0.043 R which makes it a member
of the bloated giant subgroup. It orbits its G3 V host star in 1.72 days. The
system has an isochronal age of 5.1 Gyr, consistent with its moderate stellar
activity as observed in the Kepler light curve and the rotation of the star of
17.2 1.6 days. From the detected secondary, we derived the day side
temperature as a function of the geometric albedo and estimated the geometrical
albedo, Ag, is in the range 0.094 to 0.013. The measured night side flux
corresponds to a night side brightness temperature of 2154 83 K, much
greater than what is expected for a planet with homogeneous heat
redistribution. From the comparison to star and planet evolution models, we
found that dissipation should operate in the deep interior of the planet. This
modeling also shows that despite its inflated radius, the planet presents a
noticeable amount of heavy elements, which accounts for a mass fraction of 0.11
0.04.Comment: 11 pages, 9 figure
Characterization of the four new transiting planets KOI-188b, KOI-195b, KOI-192b, and KOI-830b
The characterization of four new transiting extrasolar planets is presented
here. KOI-188b and KOI-195b are bloated hot Saturns, with orbital periods of
3.8 and 3.2 days, and masses of 0.25 and 0.34 M_Jup. They are located in the
low-mass range of known transiting, giant planets. KOI-192b has a similar mass
(0.29 M_Jup) but a longer orbital period of 10.3 days. This places it in a
domain where only a few planets are known. KOI-830b, finally, with a mass of
1.27 M_Jup and a period of 3.5 days, is a typical hot Jupiter. The four planets
have radii of 0.98, 1.09, 1.2, and 1.08 R_Jup, respectively. We detected no
significant eccentricity in any of the systems, while the accuracy of our data
does not rule out possible moderate eccentricities. The four objects were first
identified by the Kepler Team as promising candidates from the photometry of
the Kepler satellite. We establish here their planetary nature thanks to the
radial velocity follow-up we secured with the HARPS-N spectrograph at the
Telescopio Nazionale Galileo. The combined analyses of the datasets allow us to
fully characterize the four planetary systems. These new objects increase the
number of well-characterized exoplanets for statistics, and provide new targets
for individual follow-up studies. The pre-screening we performed with the
SOPHIE spectrograph at the Observatoire de Haute-Provence as part of that study
also allowed us to conclude that a fifth candidate, KOI-219.01, is not a planet
but is instead a false positive.Comment: 13 pages, 4 figures, 6 tables, final version accepted for publication
in A&
SOPHIE velocimetry of Kepler transit candidates. XV. KOI-614b, KOI-206b, and KOI-680b: a massive warm Jupiter orbiting a G0 metallic dwarf and two highly inflated planets with a distant companion around evolved F-type stars
We report the validation and characterization of three new transiting
exoplanets using SOPHIE radial velocities: KOI-614b, KOI-206b, and KOI-680b.
KOI-614b has a mass of and a radius of
, and it orbits a G0, metallic
([Fe/H]=) dwarf in 12.9 days. Its mass and radius are familiar and
compatible with standard planetary evolution models, so it is one of the few
known transiting planets in this mass range to have an orbital period over ten
days. With an equilibrium temperature of K, this places
KOI-614b at the transition between what is usually referred to as "hot" and
"warm" Jupiters. KOI-206b has a mass of and a
radius of , and it orbits a slightly evolved F7-type
star in a 5.3-day orbit. It is a massive inflated hot Jupiter that is
particularly challenging for planetary models because it requires unusually
large amounts of additional dissipated energy in the planet. On the other hand,
KOI-680b has a much lower mass of and requires less
extra-dissipation to explain its uncommonly large radius of . It is one of the biggest transiting planets characterized so far,
and it orbits a subgiant F9-star well on its way to the red giant stage, with
an orbital period of 8.6 days. With host stars of masses of
and , respectively, KOI-206b,
and KOI-680b are interesting objects for theories of formation and survival of
short-period planets around stars more massive than the Sun. For those two
targets, we also find signs of a possible distant additional companion in the
system
III.5 Stellar classification in CoRoT faint stars fields
This book is dedicated to all the people interested in the CoRoT mission and the beautiful data that were delivered during its six year duration. Either amateurs, professional, young or senior researchers, they will find treasures not only at the time of this publication but also in the future twenty or thirty years. It presents the data in their final version, explains how they have been obtained, how to handle them, describes the tools necessary to understand them, and where to find them. It also highlights the most striking first results obtained up to now. CoRoT has opened several unexpected directions of research and certainly new ones still to be discovered
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