Ready for O4 II: GRANDMA Observations of Swift GRBs during eight-weeks of Spring 2022

We present a campaign designed to train the GRANDMA network and its infrastructure to follow up on transient alerts and detect their early afterglows. In preparation for O4 II campaign, we focused on GRB alerts as they are expected to be an electromagnetic counterpart of gravitational-wave events. Our goal was to improve our response to the alerts and start prompt observations as soon as possible to better prepare the GRANDMA network for the fourth observational run of LIGO-Virgo-Kagra (which started at the end of May 2023), and future missions such as SM. To receive, manage and send out observational plans to our partner telescopes we set up dedicated infrastructure and a rota of follow-up adcates were organized to guarantee round-the-clock assistance to our telescope teams. To ensure a great number of observations, we focused on Swift GRBs whose localization errors were generally smaller than the GRANDMA telescopes' field of view. This allowed us to bypass the transient identification process and focus on the reaction time and efficiency of the network. During 'Ready for O4 II', 11 Swift/INTEGRAL GRB triggers were selected, nine fields had been observed, and three afterglows were detected (GRB 220403B, GRB 220427A, GRB 220514A), with 17 GRANDMA telescopes and 17 amateur astronomers from the citizen science project Kilonova-Catcher. Here we highlight the GRB 220427A analysis where our long-term follow-up of the host galaxy allowed us to obtain a photometric redshift of $z=0.82\pm0.09$, its lightcurve elution, fit the decay slope of the afterglows, and study the properties of the host galaxy

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Follow up of GW170817 and its electromagnetic counterpart by Australian-led observing programmes

The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor

Multi-messenger Observations of a Binary Neutron Star Merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ȯ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p

Comparaison de la qualité de vie et des comorbidités psychiatriques chez les patients souffrant de mouvements anormaux fonctionnels et organiques

Background: patients with functional movement disorders (FMD) often report disability and have psychiatric comorbidities (PC). However, few studies compared their quality of life (QoL) and their PC to those of patients with organic movement disorders (OMD). Objectives: to compare the QoL and PC of patients with FMD to those of parkinsonian and dystonic patients. Methods : 30 and 21 patients with FMD were respectively compared to 31 sex- and age-matched parkinsonian patients and 21 sex- and age-matched dystonic patients. QoL was assessed on the Parkinson’s Disease Summary Index (PDSI) and the Sheehan Disability Scale (SDS). PC were screened with the Mini International Neuropsychiatric Interview (MINI) and the Hospital Anxiety and Depression Scale (HADS). Traumatic events were screened with the Composite International Diagnostic Interview (CIDI). Results: the QoL of patients with FMD was as impaired as that of parkinsonian patients on PDSI (38.3 vs 32.2; p = 0.61) and SDS (18.0 vs 13.5; p = 0.37) and more impaired than dystonic patients on PDSI (42.1 vs 25.1; p = 0.003) but not on SDS (19.0 vs 15.0; p = 0.28). The prevalence of PC was similar in all three groups for anxiety (p = 1.0 and 0.58) and depression (p = 0.77 and 0.77). The three groups reported as many traumatic events (p = 0.75 and 0.58). Conclusion: patients with FMD have a QoL that is at least as impaired as that of patients with OMD, without having more PC. A global management of these patients is necessary.Contexte : les patients ayant des mouvements anormaux fonctionnels (MAF) rapportent souvent un handicap et ont des comorbidités psychiatriques (CP). Or, peu d’études ont comparé leur qualité de vie (QdV) et leurs CP à celles de patients ayant des mouvements anormaux organiques (MAO). Objectifs : comparer la QdV et les CP de patients ayant des MAF à celles de patients parkinsoniensou dystoniques.Matériel et méthodes : 30 et 21 patients ayant des MAF ont été comparés respectivement à 30 patients parkinsoniens et 21 patients dystoniques appariés en âge et en sexe. La QdV était évaluée sur le Parkinson’s Disease Summary Index (PDSI) et le Sheehan Disability Scale (SDS). Les CP étaient dépistées par le Mini International Neuropsychiatric Interview (MINI) et l’Hospital Anxiety and Depression Scale (HADS). Les événements traumatisants étaient dépistés par le Composite International Diagnostic Interview (CIDI). Résultats : la QdV des patients ayant des MAF était aussi altérée que celle des patients parkinsoniens sur le PDSI (38,3 vs 32,2 ; p = 0,61) et sur le SDS (18,0 vs 13,5 ; p = 0,37) et plus altérée que les patients dystoniques sur le PDSI (42,1 vs 25,1 ; p = 0,003) mais pas sur le SDS (19,0 vs 15,0 ; p = 0,28). La prévalence des CP était identique dans les trois groupes pour l’anxiété (p = 1,0 et 0,58) et la dépression (p = 0,77 et 0,77). Les trois groupes ont rapporté autant d’événements traumatisants (p = 0,75 et 0,58). Conclusion : les patients ayant des MAF ont une QdV au moins aussi altérée que celle de patients ayant des MAO, sans pour autant avoir plus de CP. Une prise en charge globale de ces patients est nécessaire

ANALYSE ET EVALUATION D'UNE CONSULTATION DE MEDECINE PSYCHOSOMATIQUE AU SEIN DU SERVICE DE MEDECINE INTERNE DU C.H.U. DE NANTES (ETUDE DE 72 CAS ENTRE 1995 ET 2000)

NANTES-BU Médecine pharmacie (441092101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

A Multivariate Functional Data Analysis of Aircraft Trajectories

While advanced methods for functional data analysis have recently been developed in the literature, applications to aircraft trajectories have remained scarce, despite operational relevance. One reason is the practical difficulties affiliated with the multivariate nature of trajectories and associated physical constraints. Indeed, an aircraft trajectory usually involves three dimensions in space (longitude, latitude, altitude) but also weather values (say wind speed and direction), each dimension having its specificities. To name a few, smoothing altitude values requires to ensure both non-negativity and boundary constraints. Wind directions have support on the unit circle. Additional to constrained smoothing challenges, phase variations are to be taken into account as flights are never of the same duration. To tackle these issues, two smoothing methods respectively based on constrained splines and asymmetric kernels are implemented on real data. For each approach, two strategies to handle the circular nature of wind directions are compared. Registration is performed. A joint pointwise test is proposed to demonstrate that delayed flights have experienced less favorable wind conditions

Hidden Markov Models and Flight Phase Identification

The use of Hidden Markov Models (HMMs) in segmenting flight phases is a compelling approach with significant implications for aviation and aerospace research. It leverages the temporal sequences of flight data to delineate various phases of an aircraft's journey, making it a valuable tool for enhancing the analysis of flight performance and safety. In this work, we implement a multivariate HMM to identify 6 flight phases: taxi, takeoff, climb, cruise, approach and rollout. We reach a median global accuracy of about 97% over a sample of several thousand flights with a very low number of decoded unlikely transitions. Regarding several performance metrics, our method is competitive with existing methods in the literature, such as fuzzy logic. Additionally, it provides, for each point of the flight, a probability of belonging to each phase. Even in situations where there are missing values in the data, HMMs remain effective, ensuring that no critical information is lost during the segmentation process. We show that HMMs work seamlessly with the fine granularity of Flight Data Recorder (FDR) data. HMMs offer remarkable flexibility and adaptability, proving particularly effective when the number or order of phases is unknown or not predetermined, as is often the case with complex flight scenarios such as helicopter flights. This adaptability is crucial for handling the diverse range of flight operations that differ from one aircraft to another. An example is given with the segmentation of an Automatic Dependent Surveillance-Broadcast (ADS-B) helicopter flight operated by the Swedish National Police

A Geostatistical framework to Interpolate Sustainable Aviation Data

In the sustainable aviation literature, it is common to rely on multiple data sets, including traffic, noise, and meteorological data. Spatial interpolation of these data is a frequent practice. This article presents a comprehensive comparison of interpolation techniques for aviation data, focusing on stochastic methods. Two primary case studies are investigated: the interpolation of noise in the vicinity of airports (two-dimensional interpolation) and the interpolation of weather values across multiple pressure layers (threedimensional interpolation). In the first case, standard geostatistical methods are particularly well-suited. The interpolation of meteorological values is more complex. The underlying physics gives rise to a trend and complex anisotropies that are challenging to estimate with the basic geostatistical framework. In the absence of outliers and if meteorological data are sampled on a sufficiently dense regular grid, trilinear interpolation performs comparably to advanced statistical methods. Otherwise, statistical methods appear to be more flexible