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Search for gravitational waves emitted from SN 2023ixf
No full textInternational audienceWe present the results of a search for gravitational-wave transients associated with core-collapse supernova SN 2023ixf, which was observed in the galaxy Messier 101 via optical emission on 2023 May 19th, during the LIGO-Virgo-KAGRA 15th Engineering Run. We define a five-day on-source window during which an accompanying gravitational-wave signal may have occurred. No gravitational waves have been identified in data when at least two gravitational-wave observatories were operating, which covered of this five-day window. We report the search detection efficiency for various possible gravitational-wave emission models. Considering the distance to M101 (6.7 Mpc), we derive constraints on the gravitational-wave emission mechanism of core-collapse supernovae across a broad frequency spectrum, ranging from 50 Hz to 2 kHz where we assume the GW emission occurred when coincident data are available in the on-source window. Considering an ellipsoid model for a rotating proto-neutron star, our search is sensitive to gravitational-wave energy and luminosity for a source emitting at 50 Hz. These constraints are around an order of magnitude more stringent than those obtained so far with gravitational-wave data. The constraint on the ellipticity of the proto-neutron star that is formed is as low as , at frequencies above Hz, surpassing results from SN 2019ejj
Speciation of Ru through A4F-MALS, Spectrophotometry UV-Visible and LDI-TOF for a 103-Ru/103m-Rh generator
No full textInternational audienceObjectives: Ruthenium is considered to be an interesting element for establishing a 103Ru/103mRh generator for Auger therapy. In radiochemical processes, Ru may be present as Ru(II), (III), (IV), (VI), (VII), or (VIII), with Ru (III) and Ru (IV) the most numerous and stable compounds [1, 2]. But a chloride solution initially contains both Ru(III) and Ru(IV) species [1]. Ru species chemical behaviors are strongly pH dependent, leading to polynuclear complexes. This tendency to form polynuclear complexes linked by oxide and hydroxide bounds is most prominent for the oxidation states +III and +IV [3]. Additionally, colloidal ruthenium hydroxides are formed by the hydrolysis of Ru(III) and Ru(IV) compounds. These polynuclear, polymeric and colloidal species are not desirable for establishing a well-controlled chromatographic 103Ru/103mRh generator.Methods: It is of utmost importance to avoid the formation of colloidal species for the use of a 103Ru/103mRh generator for Auger therapy. Asymmetrical Flow-Field- Flow Fractionation (AF4) has been be used to analyze different Ru(IV) solutions in different HCl concentrations to check the presence / absence of Ru colloids in order to establish suitable HCl conditions for elution, i.e. keeping monomeric Ru(IV) on the resin when avoiding Ru colloids formation. The speciation of Ru was carried out by Asymmetrical Flow Field-Flow Fractionation (AF4) coupled to a Multi-Angle Light Scattering (MALS) detector. Results: The presence of ruthenium colloid in aqueous solution was evidenced with a polymodal and polydisperse profile. Ruthenium colloids formation appears before a precipitation within RuO2, visible at pH 2 and pH 4. Ruthenium colloids observed in the supernatant seems to be more stable at pH 4 than at pH 2 since no colloid has been observed at pH 2 either by MALS or by UV. These data lead to assume that it is possible to make generator in acidic pH conditions because in this case, all the species are in solution, and no colloids are formed 1. Lawrence MAW, Bullock JL, Holder AA (2017) Basic Coordination Chemistry of Ruthenium. In: Browne WR, Holder AA, Lawrence MA, et al (eds) Ruthenium Complexes. Wiley, Germany2. Epperson CE (1975) Generator Separation of Ru-103/Rh-103m. University of Perdue, PhD Thesis3. Niedrach LW, Tevebaugh AD (1951) The Polarography of Ruthenium (IV) in Perchloric Acid Solutions. J Am Chem Soc 73:2835–2837. https://doi.org/10.1021/ja01150a11
First Search for Light Dark Matter in the Neutrino Fog with XENONnT
No full textInternational audienceWe search for dark matter (DM) with a mass [3,12] using an exposure of 3.51 with the XENONnT experiment. We consider spin-independent, spin-dependent, momentum-dependent, mirror DM, and self-interacting DM with a light mediator coupling to Standard Model particles. Using a lowered energy threshold compared to the previous WIMP search, a blind analysis of [0.5, 5.0] nuclear recoil events reveals no significant signal excess over the background. XENONnT excludes spin-independent DM-nucleon cross sections at confidence level for 6 DM. The solar neutrino coherent elastic neutrino-nucleus scattering background accounts for approximately half of the background in the signal region. In the considered mass range, the DM sensitivity approaches the 'neutrino fog', the limitation where neutrinos produce a signal that is indistinguishable from that of light DM-xenon nucleus scattering
Recording and reporting of ultra-high dose rate “FLASH” delivery for preclinical and clinical settings
No full textInternational audienceTreatments at ultra-high dose rate (UHDR) have the potential to improve the therapeutic index of radiation therapy (RT) by sparing normal tissues compared to conventional dose rate irradiations. Insufficient and inconsistent reporting in physics and dosimetry of preclinical and translational studies may have contributed to a reproducibility crisis of radiobiological data in the field. Consequently, the development of a common terminology, as well as common recording, reporting, dosimetry, and metrology standards is required. In the context of UHDR irradiations, the temporal dose delivery parameters are of importance, and under-reporting of these parameters is also a concern.This work proposes a standardization of terminology, recording, and reporting to enhance comparability of both preclinical and clinical UHDR studies and and to allow retrospective analyses to aid the understanding of the conditions which give rise to the FLASH effect
Measurements of inclusive J/ production at midrapidity and forward rapidity in PbPb collisions at = 5.02 TeV
No full textInternational audienceThe measurements of the inclusive J/ yield at midrapidity () and forward rapidity (2.5 4) in PbPb collisions at TeV with the ALICE detector at the LHC are reported. The inclusive J/ production yields and nuclear modification factors, , are measured as a function of the collision centrality, J/ transverse momentum (), and rapidity. The J/ average transverse momentum and squared transverse momentum ( and ) are evaluated as a function of the centrality at midrapidity. Compared to the previous ALICE publications, here the entire PbPb collisions dataset collected during the LHC Run 2 is used, which improves the precision of the measurements and extends the coverage. The -integrated shows a hint of an increasing trend towards unity from semicentral to central collisions at midrapidity, while it is flat at forward rapidity. The -differential shows a strong suppression at high with less suppression at low where it reaches a larger value at midrapidity compared to forward rapidity. The ratio of the -integrated yields of J/ to those of D mesons is reported for the first time for the central and semicentral event classes at midrapidity. Model calculations implementing charmonium production via the coalescence of charm quarks and antiquarks during the fireball evolution (transport models) or in a statistical approach with thermal weights are in good agreement with the data at low . At higher , the data are well described by transport models and a model based on energy loss in the strongly-interacting medium produced in nuclear collisions at the LHC
Semi-inclusive single-jet production in DIS at next-to-leading order in the Color Glass Condensate
No full textInternational audienceWithin the Color Glass Condensate (CGC) effective field theory, we derive the next-to-leading order (NLO) cross-section for the single-jet semi-inclusive cross-section in deep inelastic scattering (DIS) at small , for both longitudinally and transversely polarized virtual photons. We provide analytic expressions, valid at finite and suitable for numerical evaluation, for both the cross-section differential in rapidity and transverse momentum and the cross-section differential in rapidity only. Our NLO formulae demonstrate that the very forward rapidity regime is plagued by large double logarithmic corrections coming from phase space constraints on soft gluons close to the kinematic threshold for jet production. A joint resummation of small- and threshold logarithms at single logarithmic accuracy is proposed to remedy the instability of the cross-section in this regime. By integrating over the single-jet phase space, we recover known results for the NLO DIS structure functions at small , previously obtained using the optical theorem
Mesures de décroissances beta avec la technique TAGS et impact sur les calculs de puissance résiduelle
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Synthesis and preclinical evaluation of BOLD-100 radiolabeled with ruthenium-97 and ruthenium-103
No full textInternational audienceBOLD-100 (formerly IT-139, KP1339), a well-established chemotherapeutic agent, is currently being investigated in clinical trials for the treatment of gastric, pancreatic, colorectal, and bile duct cancer. Despite numerous studies, the exact mode of action is still the subject of discussions. Radiolabeled BOLD-100 could be a powerful tool to clarify pharmacokinetic pathways of the compound and to predict therapy responses in patients using nuclear molecular imaging prior to the therapy. In this study, the radiosyntheses of carrier-added (c.a.) [97/103Ru]BOLD-100 were performed with the two ruthenium isotopes ruthenium-103 (103Ru; β−, γ) and ruthenium-97 (97Ru; EC, γ), of which in particular the latter isotope is suitable for imaging by single-photon emission computed tomography (SPECT). To identify the best tumor-to-background ratio for diagnostic imaging, biodistribution studies were performed with two different injected doses of c.a. [103Ru]BOLD-100 (3 and 30 mg kg−1) in Balb/c mice bearing CT26 allografts over a time period of 72 h. Additionally, ex vivo autoradiography of the tumors (24 h p.i.) was conducted. Our results indicate that the higher injected dose (30 mg kg−1) leads to more unspecific accumulation of the compound in non-targeted tissue, which is likely due to an overload of the albumin transport system. It was also shown that lower amounts of injected c.a. [103Ru]BOLD-100 resulted in a relatively higher tumor uptake and, therefore, a better tumor-to-background ratio, which are encouraging results for future imaging studies using c.a. [97Ru]BOLD-100
Quarkonium dynamics in the quantum Brownian regime with non-abelian quantum master equations
No full textInternational audienceWe present numerical solutions in a one-dimensional setting of quantum master equations that have been recently derived. We focus on the dynamics of a single heavy quark-antiquark pair in a Quark-Gluon Plasma in thermal equilibrium, in the so-called quantum Brownian regime where the temperature of the plasma is large in comparison with the spacing between the energy levels of the system. The one-dimensional potential used in the calculations has been adjusted so as to produce numbers that are relevant for the phenomenology of the charmonium. The equations are solved using different initial states and medium configurations. Various temperature regimes are studied and the effects of screening and collisions thoroughly analyzed. Technical features of the equations are analyzed. The contributions of the different operators that control the evolution are discussed as a function of the temperature. Some phenomenological consequences are addressed