0254: Updated reference levels for radiation doses to patients undergoing coronary angiography and coronary percutaneous interventions: the RAY’ACT2 study

PurposeThe RAY’ACT project is a nationwide, multicentre survey program aimed at evaluating patient radiation protection (RP) during coronary angiography (CA) and percutaneous coronary interventions (PCI) in French non-university public hospitals, which represent>30% of the national activity for PCIs, and 60% of the emergency cases. We present the updated reference levels based on the results of the second survey conducted in 2013 (RAY’ACT2).MethodsRP parameters from 48,547 CAs and 40,026 PCIs performed at 61 centres during 2013 and routinely registered in professional software were extracted and analysed retrospectively. Kerma-area product (KAP), fluoroscopy time (FT), number of acquired frames (Nb F) and runs (NR), and total Air Kerma at interventional reference point (KA, r) were analysed separately for CAs and PCIs (elective and ad hoc pooled). All procedures of the year were included.ResultsThe table shows the medians (Q1-Q3) of the RP parameters, updated RLs based on the 75th percentiles of the values for CA and PCI (bold), and previous RLs (RAY’ACT1, 2010).ConclusionsBetween 2010 and 2013, a 20 to 30% decrease was observed in medians and Reference Levels (Q3) for main RP parameters, including KAP and total Air Kerma.Abstract 0254 – Table: Results2013 (RAY’ACT2) 61 centres2010 (RAY’ACT1) 44 centresCAN=48,547N=31,066KAP (Gy.cm²)20.9 (11.8-35.7)27.2 (15.5-45.2)FT (min)3.3 (2.1-5.7)3.7 (2.3-6.3)Nb Frames404 (284-566)553 (388-769)KA,r (mGy)294 (164-498)421 (240-695)PCIN=40,026N=25,356KAP (Gy.cm²)45.2 (25.6-77.6)56.8 (32.8-94.6)FT (min)9.8 (6.3-15.4)10.3 (6.7-16.2)Nb Frames676 (465-960)837 (578-1193)KA,r (mGy)747 (421-1285)1052 (589-1788

A wide planetary-mass companion to a young low-mass brown dwarf in Ophiuchus

We present the discovery of a planetary-mass companion to CFHTWIR-Oph 98, a low-mass brown dwarf member of the young Ophiuchus star-forming region, with a wide 200 au separation (1farcs46). The companion was identified using Hubble Space Telescope images, and confirmed to share common proper motion with the primary using archival and new ground-based observations. Based on the very low probability of the components being unrelated Ophiuchus members, we conclude that Oph 98 AB forms a binary system. From our multiband photometry, we constrain the primary to be an M9–L1 dwarf, and the faint companion to have an L2–L6 spectral type. For a median age of 3 Myr for Ophiuchus, fits of evolutionary models to measured luminosities yield masses of 15.4 ± 0.8 MJup for Oph 98 A and 7.8 ± 0.8 MJup for Oph 98 B, with respective effective temperatures of 2320 ± 40 K and 1800 ± 40 K. For possible system ages of 1–7 Myr, masses could range from 9.6–18.4 MJup for the primary, and from 4.1–11.6 MJup for the secondary. The low component masses and very large separation make this binary the lowest binding energy system imaged to date, indicating that the outcome of low-mass star formation can result in such extreme, weakly bound systems. With such a young age, Oph 98 AB extends the growing population of young free-floating planetary-mass objects, offering a new benchmark to refine formation theories at the lowest masses

Near-Infrared Thermal Emission from the Hot Jupiter TrES-2b: Ground-Based Detection of the Secondary Eclipse

We present near-infrared Ks-band photometry bracketing the secondary eclipse of the hot Jupiter TrES-2b using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope. We detect its thermal emission with an eclipse depth of 0.062 +/- 0.012% (5-sigma). Our best-fit secondary eclipse is consistent with a circular orbit (a 3-sigma upper limit on the eccentricity, e, and argument or periastron, omega, of |ecos(omega)| < 0.0090), in agreement with mid-infrared detections of the secondary eclipse of this planet. A secondary eclipse of this depth corresponds to a day-side Ks-band brightness temperature of TB = 1636 +/- 88 K. Our thermal emission measurement when combined with the thermal emission measurements using Spitzer/IRAC from O'Donovan and collaborators suggest that this planet exhibits relatively efficient day to night-side redistribution of heat and a near isothermal dayside atmospheric temperature structure, with a spectrum that is well approximated by a blackbody. It is unclear if the atmosphere of TrES-2b requires a temperature inversion; if it does it is likely due to chemical species other than TiO/VO as the atmosphere of TrES-2b is too cool to allow TiO/VO to remain in gaseous form. Our secondary eclipse has the smallest depth of any detected from the ground at around 2 micron to date.Comment: ApJ accepted, 8 pages, 9 figures, in emulateapj format

Broadband Transmission Spectroscopy of the super-Earth GJ 1214b suggests a Low Mean Molecular Weight Atmosphere

We used WIRCam on CFHT to observe four transits of the super-Earth GJ 1214b in the near-infrared. For each transit we observed in two bands nearly-simultaneously by rapidly switching the WIRCam filter wheel back and forth for the duration of the observations. By combining all our J-band (~1.25 microns) observations we find a transit depth in this band of 1.338\pm0.013% - a value consistent with the optical transit depth reported by Charbonneau and collaborators. However, our best-fit combined Ks-band (~2.15 microns) transit depth is deeper: 1.438\pm0.019%. Formally our Ks-band transits are deeper than the J-band transits observed simultaneously by a factor of 1.072\pm0.018 - a 4-sigma discrepancy. The most straightforward explanation for our deeper Ks-band depth is a spectral absorption feature from the limb of the atmosphere of the planet; for the spectral absorption feature to be this prominent the atmosphere of GJ 1214b must have a large scale height and a low mean molecular weight. That is, it would have to be hydrogen/helium dominated and this planet would be better described as a mini-Neptune. However, recently published observations from 0.78 - 1.0 microns, by Bean and collaborators, show a lack of spectral features and transit depths consistent with those obtained by Charbonneau and collaborators. The most likely atmospheric composition for GJ 1214b that arises from combining all these observations is less clear; if the atmosphere of GJ 1214b is hydrogen/helium dominated then it must have either a haze layer that is obscuring transit depth differences at shorter wavelengths, or significantly different spectral features than current models predict. Our observations disfavour a water-world composition, but such a composition will remain a possibility until observations reconfirm our deeper Ks-band transit depth or detect features at other wavelengths. [Abridged]Comment: ApJ accepted. 12 pages, 6 figures, in EmulateApJ forma

Near-infrared Thermal Emission Detections of a number of hot Jupiters and the Systematics of Ground-based Near-infrared Photometry

We present detections of the near-infrared thermal emission of three hot Jupiters and one brown-dwarf using the Wide-field Infrared Camera (WIRCam) on the Canada-France-Hawaii Telescope (CFHT). These include Ks-band secondary eclipse detections of the hot Jupiters WASP-3b and Qatar-1b and the brown dwarf KELT-1b. We also report Y-band, $K_{CONT}$-band, and two new and one reanalyzed Ks-band detections of the thermal emission of the hot Jupiter WASP-12b. We present a new reduction pipeline for CFHT/WIRCam data, which is optimized for high precision photometry. We also describe novel techniques for constraining systematic errors in ground-based near-infrared photometry, so as to return reliable secondary eclipse depths and uncertainties. We discuss the noise properties of our ground-based photometry for wavelengths spanning the near-infrared (the YJHK-bands), for faint and bright-stars, and for the same object on several occasions. For the hot Jupiters WASP-3b and WASP-12b we demonstrate the repeatability of our eclipse depth measurements in the Ks-band; we therefore place stringent limits on the systematics of ground-based, near-infrared photometry, and also rule out violent weather changes in the deep, high pressure atmospheres of these two hot Jupiters at the epochs of our observations.Comment: 27 pages, 23 figures, ApJ submitted June 16th, 2014. Version revised to address referee comment

Near-Infrared Thermal Emission from TrES-3b: A Ks-band detection and an H-band upper limit on the depth of the secondary eclipse

We present H and Ks-band photometry bracketing the secondary eclipse of the hot Jupiter TrES-3b using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope. We detect the secondary eclipse of TrES-3b with a depth of 0.133+/-0.017% in Ks-band (8-sigma) - a result in sharp contrast to the eclipse depth reported by de Mooij & Snellen. We do not detect its thermal emission in H-band, but place a 3-sigma limit on the depth of the secondary eclipse in this band of 0.051%. A secondary eclipse of this depth in Ks requires very efficient day-to-nightside redistribution of heat and nearly isotropic reradiation, conclusion that is in agreement with longer wavelength, mid-infrared Spitzer observations. Our 3-sigma upper-limit on the depth of our H-band secondary eclipse also argues for very efficient redistribution of heat and suggests that the atmospheric layer probed by these observations may be well homogenized. However, our H-band upper limit is so constraining that it suggests the possibility of a temperature inversion at depth, or an absorbing molecule, such as methane, that further depresses the emitted flux at this wavelength. The combination of our near-infrared measurements and those obtained with Spitzer suggest that TrES-3b displays a near isothermal dayside atmospheric temperature structure, whose spectrum is well approximated by a blackbody. We emphasize that our strict H-band limit is in stark disagreement with the best-fit atmospheric model that results from longer wavelength observations only, thus highlighting the importance of near-infrared observations at multiple wavelengths in addition to those returned by Spitzer in the mid-infrared to facilitate a comprehensive understanding of the energy budgets of transiting exoplanets.Comment: ApJ accepted, 8 pages, 7 figures, in EmulateApJ forma

Near-infrared Thermal Emission from WASP-12b: detections of the secondary eclipse in Ks, H & J

We present Ks, H & J-band photometry of the very highly irradiated hot Jupiter WASP-12b using the Wide-field Infrared Camera on the Canada-France-Hawaii telescope. Our photometry brackets the secondary eclipse of WASP-12b in the Ks and H-bands, and in J-band starts in mid-eclipse and continues until well after the end of the eclipse. We detect its thermal emission in all three near-infrared bands. Our secondary eclipse depths are 0.309 +/- 0.013% in Ks-band (24-sigma), 0.176 +/- 0.020% in H-band (9-sigma) and 0.131 +/- 0.028% in J-band (4-sigma). All three secondary eclipses are best-fit with a consistent phase that is compatible with a circular orbit. By combining our secondary eclipse times with others published in the literature, as well as the radial velocity and transit timing data for this system, we show that there is no evidence that WASP-12b is precessing at a detectable rate, and show that its orbital eccentricity is likely zero. Our thermal emission measurements also allow us to constrain the characteristics of the planet's atmosphere; our Ks-band eclipse depth argues in favour of inefficient day to nightside redistribution of heat and a low Bond albedo for this very highly irradiated hot Jupiter. The J and H-band brightness temperatures are slightly cooler than the Ks-band brightness temperature, and thus hint at the possibility of a modest temperature inversion deep in the atmosphere of WASP-12b; the high pressure, deep atmospheric layers probed by our J and H-band observations are likely more homogenized than the higher altitude layer. Lastly, our best-fit Ks-band eclipse has a marginally longer duration than would otherwise be expected; this may be tentative evidence for material being tidally stripped from the planet - as was predicted for this system by Li & collaborators, and for which observational confirmation was recently arguably provided by Fossati & collaborators.Comment: AJ accepted. 12 pages, 11 figures, in EmulateApJ format. Version 2 removes two figures that were added by mistak

The effect of dynamic recrystallisation on the rheology and microstructures of partially molten rocks

This work was founded by the joint project “Rheology of the continental crust in collision”, funded by the Procope scheme of PHC Egide in France and by the DAAD PPP scheme in Germany. M-GL acknowledges the support of the Juan de la Cierva programme of the Government of Spain’s Ministry for Science, Innovation and Universities. EGR acknowledges the support of the Beatriu de Pinós programme of the Government of Catalonia's Secretariat for Universities and Research of the Department of Economy and Knowledge (2016 BP 00208). This work benefited from discussions with Pi L. Jolivet and E. Burov within the ERC project RHEOLITH. We thank Elisabetta Mariani and Marcin Dabrowski for their helpful comments, together with the editorial guidance of Dave Healy and Bill Dunne.Peer reviewedPostprin