534 research outputs found
Un console Milano e l'impero che muore
No full textThe tome is the biography of a pretorian prefect during the years 397-399 and it is pieced togheter thanks to the few evidence about the officer and the laws that the Emperor Onorio refers to him. Flavius Manlius Theodorus, consul during the year 399, lives and works in Milan, which was the West Empire capital in that period. We are trying to make a portrait of an author who was important for the varied and complex imperial legislation included in the Theodosian code through the rebuilt of his life and his officer career
Metallicity of M dwarfs: The link to exoplanets
No full textAbstractThe determination of the stellar parameters of M dwarfs is of prime importance in the fields of galactic, stellar and planetary astronomy. M stars are the least studied galactic component regarding their fundamental parameters. Yet, they are the most numerous stars in the galaxy and contribute to most of its total (baryonic) mass. In particular, we are interested in their metallicity in order to study the star-planet connection and to refine the planetary parameters. As a preliminary result we present a test of the metallicity calibrations of Bonfils et al. (2005), Johnson & Apps (2009), and Schlaufman & Laughlin (2010) using a new sample of 17 binaries with precise V band photometry.</jats:p
Les limites à l'attribution des prestations familiales aux parents d'enfants étrangers
No full textInternational audienceNote sous Cass. ass. plén. 3 juin 2011, Epoux X... c/ CAF d'Ille-et-Vilaine, n° 09-69.052, D. 2011. 1625, obs. C. de la Première présidence ; ibid. 1995, obs. P. Bonfils et A. Gouttenoire ; AJ famille 2011. 375, ; CAF de Paris c/ M. X..., n° 09-71.352, D. 2011. 1995, obs. P. Bonfils et A. Gouttenoire ; AJ famille 2011. 375, obs. I. Say
Liberté du commerce et de l'industrie. Professions réglementées, référé-liberté
No full textInternational audience(CE, ord. du 1er mars 2002, M. X. Bonfils, Req. n° 243651
Les limites à l'attribution des prestations familiales aux parents d'enfants étrangers
No full textInternational audienceNote sous Cass. ass. plén. 3 juin 2011, Epoux X... c/ CAF d'Ille-et-Vilaine, n° 09-69.052, D. 2011. 1625, obs. C. de la Première présidence ; ibid. 1995, obs. P. Bonfils et A. Gouttenoire ; AJ famille 2011. 375, ; CAF de Paris c/ M. X..., n° 09-71.352, D. 2011. 1995, obs. P. Bonfils et A. Gouttenoire ; AJ famille 2011. 375, obs. I. Say
Metallicity
No full textThe metallicity measures the fraction of the star that is made of elements heavier than
helium. It is intimately related to the stellar structure and composition and thus plays
an important role in a broad range of astrophysical cases, from stellar populations to
planet formation. This chapter aims to review the recent observational efforts to measure
the metallicity of M dwarfs and to screen few astrophysical cases which have benefited
from quantitative metallicity analysis
Oronoqua deina Fennah 1947
No full textOronoqua deina Fennah, 1947 (Figs 1A; 2 A-C; 3A; 4; 5) Oronoqua deina Fennah, 1947: 91, 92, pl. V, figs 1-7. HOLOTYPE. — Guyana. Oronoqua River, 16.X.1937, ♀ (BMNH, BM 1938-319). OTHER MATERIAL EXAMINED. — French Guiana. Petit Saut, 8.XI.1994, Roubaud leg., 1 ♂ (MNHN). — Piste de Kaw, 23.VII.1993, Roubaud leg., 1 ♀ (MNHN). — Montagne de Kaw, 17-23.VIII.1994, Roubaud leg., 1 ♀ (MNHN). DISTRIBUTION. — Guyana and French Guiana. DESCRIPTION Total length (from apex of coryphe to apex of fore wings): male 11.2 mm, females 12.5-13.0 mm. Male genitalia (Fig. 5) Pygofer with convex hind margin (Fig. 5G). Anal tube wide medially, narrowing apically (Fig. 5G), lateral margins and apex turned down (Fig. 5D). Anal column long (0.4 times as long as anal tube). Phallobase in shape of a weakly sclerotized sac subapically, with denticles (Fig. 5A). Ventral phallobase lobe long and wide, weakly narrowing apically, with apical concavity. Aedeagus with pair of long and narrow, acuminate ventral hooks. Connective bowl-shaped. Style with convex hind margin. Capitulum of style long and narrow, lateral tooth quadrate (Fig. 5E, F).Published as part of Gnezdilov, Vladimir M., Bonfils, Jacques, Aberlenc, Henri-Pierre & Basset, Yves, 2010, Review of the Neotropical genus Oronoqua Fennah, 1947 (Insecta, Hemiptera, Issidae), pp. 247-257 in Zoosystema 32 (2) on page 250, DOI: 10.5252/z2010n2a3, http://zenodo.org/record/452098
A super-Earth on an eccentric orbit moving in and out of the habitable zone,
No full textContext.
Statistical analyses based on
Kepler
data show that most of the early-type M dwarfs host multi-planet systems consisting of Earth- to sub-Neptune-sized planets with orbital periods of up to ~250 days, and that at least one such planet is likely located within the habitable zone. M dwarfs are therefore primary targets to search for potentially habitable planets in the solar neighbourhood.
Aims.
We investigated the presence of planetary companions around the nearby (7.6 pc) and bright (
V
= 9 mag) early-type M dwarf Gl 514, analysing 540 radial velocities collected over nearly 25 yr with the HIRES, HARPS, and CARMENES spectrographs.
Methods.
The data are affected by time-correlated signals at the level of 2–3 m s
−1
due to stellar activity, which we filtered out, testing three different models based on Gaussian process regression. As a sanity cross-check, we repeated the analyses using HARPS radial velocities extracted with three different algorithms. We used HIRES radial velocities and
Hipparcos-Gaia
astrometry to put constraints on the presence of long-period companions, and we analysed TESS photometric data.
Results.
We find strong evidence that Gl 514 hosts a super-Earth on a likely eccentric orbit, residing in the conservative habitable zone for nearly 34% of its orbital period. The planet Gl 514b has minimum mass
m
b
sin
i
b
= 5.2 ± 0.9
M
⊕
, orbital period
P
b
= 140.43 ± 0.41 days, and eccentricity
e
b
= 0.45
−0.14
+0.15
. No evidence for transits is found in the TESS light curve. There is no evidence for a longer period companion in the radial velocities and, based on astrometry, we can rule out a ~0.2
M
Jup
planet at a distance of ~3–10 astronomical units, and massive giant planets and brown dwarfs out to several tens of astronomical units. We discuss the possible presence of a second low-mass companion at a shorter distance from the host than Gl 514 b.
Conclusions.
Gl 514 b represents an interesting science case for studying the habitability of planets on eccentric orbits. We advocate for additional spectroscopic follow-up to get more accurate and precise planetary parameters. Further follow-up is also needed to investigate the presence of additional planetary signals of less than 1 m s
−1
Reassessment of the putative habitable zone planet GJ 832c
No full textContext.
Gliese-832 (GJ 832) is an M2V star hosting a massive planet on a decade-long orbit, GJ 832b, discovered by radial velocity (RV). Later, a super Earth or mini-Neptune orbiting within the stellar habitable zone was reported (GJ 832c). The recently determined stellar rotation period (45.7 ± 9.3 days) is close to the orbital period of putative planet c (35.68 ± 0.03 days).
Aims.
We aim to confirm or dismiss the planetary nature of the RV signature attributed to GJ 832c, by adding 119 new RV data points, new photometric data, and an analysis of the spectroscopic stellar activity indicators. Additionally, we update the orbital parameters of the planetary system and search for additional signals.
Methods.
We performed a frequency content analysis of the RVs to search for periodic and stable signals. Radial velocity time series were modelled with Keplerians and Gaussian process (GP) regressions alongside activity indicators to subsequently compare them within a Bayesian framework.
Results.
We updated the stellar rotational period of GJ 832 from activity indicators, obtaining 37.5
+1.4
-1.5
days, improving the precision by a factor of 6. The new photometric data are in agreement with this value. We detected an RV signal near 18 days (FAP < 4.6%), which is half of the stellar rotation period. Two Keplerians alone fail at modelling GJ 832b and a second planet with a 35-day orbital period. Moreover, the Bayesian evidence from the GP analysis of the RV data with simultaneous activity indices prefers a model without a second Keplerian, therefore negating the existence of planet c
Discovery of a hot, transiting, Earth-sized planet and a second temperate, non-transiting planet around the M4 dwarf GJ 3473 (TOI-488)
No full textWe present the confirmation and characterisation of GJ 3473 b (G 50–16, TOI-488.01), a hot Earth-sized planet orbiting an M4 dwarf star, whose transiting signal ( P = 1.1980035 ± 0.0000018 d) was first detected by the Transiting Exoplanet Survey Satellite (TESS). Through a joint modelling of follow-up radial velocity observations with CARMENES, IRD, and HARPS together with extensive ground-based photometric follow-up observations with LCOGT, MuSCAT, and MuSCAT2, we determined a precise planetary mass, M b = 1.86 ± 0.30 M ⊕ , and radius, R b = 1.264 ± 0.050 R ⊕ . Additionally, we report the discovery of a second, temperate, non-transiting planet in the system, GJ 3473 c, which has a minimum mass, M c sin i = 7.41 ± 0.91 M ⊕ , and orbital period, P c = 15.509 ± 0.033 d. The inner planet of the system, GJ 3473 b, is one of the hottest transiting Earth-sized planets known thus far, accompanied by a dynamical mass measurement, which makes it a particularly attractive target for thermal emission spectroscopy
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