GW170817: Swift UV detection of a blue kilonova, and improving the search in O3

2017 ◽  
Vol 13 (S338) ◽  
pp. 53-60
Author(s):  
Aaron Tohuvavohu ◽  
Jamie A. Kennea ◽  
Keyword(s):  
Health And Safety ◽  
X Ray ◽  
Operational Capabilities ◽  
Observation Strategy ◽  
Ongoing Work ◽  
The Galaxy ◽  
Multi Wavelength ◽  
Flexible Planning ◽  
The Impact

AbstractSwift’s rapid slewing, flexible planning, and multi-wavelength instruments make it the most capable space-based follow-up engine for finding poorly localized sources. During O1 and O2 Swift successfully tiled hundreds of square-degrees of sky in the LVC localization regions, searching for, and identifying, possible X-ray and UV/O transients in the field. Swift made important contributions to the discovery and characterization of the kilonova AT 2017gfo, discovering the UV emission and providing the deepest X-ray upper limits in the first 24 hours after the trigger, strongly constraining the dynamics and geometry of the counterpart. Swift tiled 92% of the galaxy convolved error region down to average X-ray flux sensitivities of 10−12 erg cm−2 s−1, significantly increasing our confidence that AT 2017gfo is indeed the counterpart to GW 170817 and sGRB 170817. However, there remains significant room for improvement of Swift’s follow-up in preparation for O3. This will take the form of both revised observation strategy based on detailed analysis of the results from O2, and significant changes to Swift’s operational capabilities. These improvements are necessary both for maximizing the likelihood that Swift finds a counterpart, and minimizing the impact that follow-up activities have on other Swift science priorities. We outline areas of improvement to the observing strategy itself for optimal tiling of the LVC localization regions. We also discuss ongoing work on operational upgrades that will decrease latency in our response time, and minimize impact on pre-planned observations, while maintaining spacecraft health and safety.

scholarly journals Impact of X-rays on CO emission from high-z galaxies

2019 ◽  
Vol 490 (4) ◽  
pp. 4502-4514 ◽  
Author(s):  
L Vallini ◽  
A G G M Tielens ◽  
A Pallottini ◽  
S Gallerani ◽  
C Gruppioni ◽  
...  
Keyword(s):  
Cosmic Ray ◽  
Ionization Rate ◽  
Joint Effect ◽  
X Rays ◽  
Giant Molecular Clouds ◽  
Line Energy ◽  
X Ray ◽  
The Galaxy ◽  
The Impact

ABSTRACT We study the impact of active galactic nuclei (AGNs) on the CO spectral line energy distribution (SLED) of high-z galaxies. In particular, we want to assess if the CO SLED can be used as a probe of AGN activity. To this purpose, we develop a semi-analytical model that takes into account the radiative transfer and the clumpy structure of giant molecular clouds where the CO lines are excited, their distribution in the galaxy disc, and the torus obscuration of the AGN radiation. We study the joint effect on the CO SLED excitation of (i) the X-ray luminosity from the AGNs (LX), (ii) the size of the molecular disc, (iii) the inclination angle (Ω) of the torus with respect to the molecular disc, and (iv) the Giant Molecular Cloud (GMC) mean density. We also discuss the possibility of an enhanced cosmic ray ionization rate (CRIR). We find that the X-ray-dominated region (XDR) generated by the AGNs in every case enhances the CO SLED for J > 5, with increasing excitation of high-J CO lines for increasing X-ray luminosity. Because high-z galaxies are compact, the XDR typically encloses the whole disc, thus its effect can be more important with respect to lower redshift objects. The impact of the XDR can be disentangled from an enhanced CRIR either if $L_\mathrm{ X}\,\gt\, 10^{44} \rm \, erg\, s^{-1}$, or if Ω ≥ 60°. We finally provide predictions on the CO(7–6)/[C ii] and CO(17–16)/[C ii] ratios as a function of LX, which can be relevant for ALMA follow-up of galaxies and quasars previously detected in [C ii].

scholarly journals The role of AGN activity in the building up of the BCG at z ∼ 1.6

2019 ◽  
Vol 15 (S356) ◽  
pp. 280-284
Author(s):  
Angela Bongiorno ◽  
Andrea Travascio
Keyword(s):  
Galaxy Cluster ◽  
Cluster Galaxy ◽  
X Ray ◽  
Groups Of Galaxies ◽  
Star Forming ◽  
The Core ◽  
The Galaxy ◽  
Multi Wavelength

AbstractXDCPJ0044.0-2033 is one of the most massive galaxy cluster at z ∼1.6, for which a wealth of multi-wavelength photometric and spectroscopic data have been collected during the last years. I have reported on the properties of the galaxy members in the very central region (∼ 70kpc × 70kpc) of the cluster, derived through deep HST photometry, SINFONI and KMOS IFU spectroscopy, together with Chandra X-ray, ALMA and JVLA radio data.In the core of the cluster, we have identified two groups of galaxies (Complex A and Complex B), seven of them confirmed to be cluster members, with signatures of ongoing merging. These galaxies show perturbed morphologies and, three of them show signs of AGN activity. In particular, two of them, located at the center of each complex, have been found to host luminous, obscured and highly accreting AGN (λ = 0.4−0.6) exhibiting broad Hα line. Moreover, a third optically obscured type-2 AGN, has been discovered through BPT diagram in Complex A. The AGN at the center of Complex B is detected in X-ray while the other two, and their companions, are spatially related to radio emission. The three AGN provide one of the closest AGN triple at z > 1 revealed so far with a minimum (maximum) projected distance of 10 kpc (40 kpc). The discovery of multiple AGN activity in a highly star-forming region associated to the crowded core of a galaxy cluster at z ∼ 1.6, suggests that these processes have a key role in shaping the nascent Brightest Cluster Galaxy, observed at the center of local clusters. According to our data, all galaxies in the core of XDCPJ0044.0-2033 could form a BCG of M* ∼ 1012Mȯ hosting a BH of 2 × 108−109Mȯ, in a time scale of the order of 2.5 Gyrs.

scholarly journals 84 Optimising The Assessment and Management of Acute Renal Colic in Secondary Care

2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
T Fonseka ◽  
R Ellis ◽  
A Gowda ◽  
L Tuckwood ◽  
A Careless ◽  
...  
Keyword(s):  
Best Practice ◽  
Current Practice ◽  
Renal Colic ◽  
Electronic Patient Records ◽  
X Ray ◽  
Improved Outcomes ◽  
Acute Renal Colic ◽  
The Impact ◽  
First Time

Abstract Aim The latest guidance in acute renal colic states that patients should have serum calcium and urate (stone bloods) measured during inpatient admission. The guidance also states that follow-up imaging should be in the form of computed tomography (CT)-, ultrasound (USS)-, or X-ray- kidney, ureters and bladder (KUB). X-ray intravenous urogram (IVU) is now considered obsolete as it can result in over-exposing patients to radiation. Aims of this 2-cycle QIP were twofold; Method Data was extracted from electronic patient records on whether or not they had stone bloods measured during admission and also what follow-up imaging was requested. In the first cycle baseline data was extracted. A stone proforma was then created, incorporating the latest guidelines. In the second cycle the impact of the stone proforma was assessed. Results The study included 119 patients. After introducing the stone proforma we were successful in improving the rate of stone bloods being measured, increasing from 13% to 53%. We were also successful in reducing the rate of performing X-ray IVU, decreasing from 25% to 14% of patients. Conclusions This QIP demonstrates that management of acute renal colic can be optimised using a stone proforma and move current practice towards best practice. This is supported by the ‘Getting it Right First Time’ (GIRFT) Urology report 2018. The third cycle is currently underway, and we hope to see further improved outcomes.

scholarly journals The nature of the unassociated 2FGL sources

2014 ◽  
Vol 10 (S313) ◽  
pp. 91-92
Author(s):  
T. Pursimo ◽  
R. Ojha ◽  
E. Ferrara ◽  
F. Acero ◽  
H. Johnston ◽  
...  
Keyword(s):  
Spectral Energy Distribution ◽  
Low Frequency ◽  
Spectral Energy ◽  
High Frequency Peak ◽  
X Ray ◽  
Frequency Peak ◽  
Inverse Compton ◽  
Multi Wavelength ◽  
Error Circle

AbstractThe majority of Fermi-LAT detected (2FGL) sources are AGN, mostly blazars. However, the second largest category in the 2FGL are unassociated sources (~30% or 575 sources), whose multi-wavelength counterpart is either inconclusive or absent. Follow-up observations and archival data at X-ray, optical, and radio frequencies suggest that many unassociated 2FGL sources are strong candidates to be AGN. Typical observed characteristics of 2FGL detected AGN include variability at all frequencies and a spectral energy distribution (SED) with two “bumps”; a low-frequency synchrotron peak in the radio to optical/X-ray region and a high-frequency peak, possibly due to synchrotron self-Compton or Inverse Compton processes, that extends up to TeV energies. We present optical follow-up observations of a sample of Fermi unassociated sources with one or more potential X-ray counterparts detected within the LAT error circle.

scholarly journals P094: Meeting patient expectations in the emergency department: preliminary findings from the preparing emergency patients and providers study

CJEM ◽  
2017 ◽  
Vol 19 (S1) ◽  
pp. S110
Author(s):  
J. Nunn ◽  
C. Cassidy ◽  
D. Chiasson ◽  
S. MacPhee ◽  
J. Curran
Keyword(s):  
Emergency Department ◽  
Response Rate ◽  
Phase 1 ◽  
Patient Expectations ◽  
Satisfaction With Care ◽  
Medical Encounter ◽  
X Ray ◽  
Phase Study ◽  
The Impact

Introduction: Effective communication to develop a shared understanding of patient expectations is critical in establishing a positive medical encounter in the emergency department (ED). However, there is limited research examining patient/caregiver expectations in the ED, and their impact on the beliefs, attitudes and behaviours during and after an ED visit. The objective of this study is to examine patient/caregiver expectations and satisfaction with care in the ED using a patient expectation questionnaire and a follow up survey. Methods: As a part of a larger 3-phase study on patient/caregiver expectations in adult and pediatric EDs, a 7-item, paper-based questionnaire was distributed to all patients and/or caregivers who presented to one of four EDs in Nova Scotia with a Canadian Triage and Acuity Scale (CTAS) score of 2 to 5. A follow-up survey was distributed to all willing participants via email to determine their satisfaction with care received in ED. Descriptive statistics were used to analyze responses. Results: Phase 1 was conducted from January to September 2016. In total, 24,788 expectation questionnaires were distributed to ED patients/caregivers, 11,571 were collected (47% response rate), and 509 patients were contacted for a follow-up survey. Preliminary analysis of 4,533 questionnaires shows the majority of patients (67.1%) made the decision by themselves to present to the ED, while others were advised by a family/friend (22%). Respondents were most worried about an injury (17.8%) followed by illness (15.6%) and expected to talk to a physician (69.9%) and receive an x-ray (39.3%). The majority of physicians (53.3%) reported the expectation tool helped in caring for the patient and 87.5% felt they met patient expectations. There were 147 patient/caregiver responses to a follow-up survey (29% response rate) and 87.1% of responders reported that ED clinicians met their expectations. Conclusion: Patient/caregivers have a variety of concerns, questions, and expectations when presenting to the ED. Obtaining expectations early in the patient encounter may provide opportunities for improved communication between clinicians and patients while enhancing satisfaction with care received. Further analysis is needed to determine the impact of the expectation questionnaire on productivity in the ED.

scholarly journals Strategy for NEO follow-up observations

2012 ◽  
Vol 10 (H16) ◽  
pp. 185-185
Author(s):  
Milos Tichy ◽  
Michaela Honkova ◽  
Jana Ticha ◽  
Michal Kocer
Keyword(s):  
Small Bodies ◽  
Time Uncertainty ◽  
The Earth ◽  
Observation Strategy ◽  
On Line ◽  
Single Night ◽  
Uncertainty Map ◽  
The Impact ◽  
Near Earth Objects

AbstractThe Near-Earth Objects (NEOs) belong to the most important small bodies in the solar system, having the capability of close approaches to the Earth and even possibility to collide with the Earth. In fact, it is impossible to calculate reliable orbit of an object from a single night observations. Therefore it is necessary to extend astrometry dataset by early follow-up astrometry. Follow-up observations of the newly discovered NEO candidate should be done over an arc of several hours after the discovery and should be repeated over several following nights. The basic service used for planning of the follow-up observations is the NEO Confirmation Page (NEOCP) maintained by the Minor Planet Center of the IAU. This service provides on-line tool for calculating geocentric and topocentic ephemerides and sky-plane uncertainty maps of these objects at the specific date and time. Uncertainty map is one of the most important information used for planning of follow-up observation strategy for given time, indicating also the estimated distance of the newly discovered object and including possibility of the impact. Moreover, observatories dealing with NEO follow-up regularly have prepared their special tools and systems for follow-up work. The system and strategy for the NEO follow-up observation used at the Klet Observatory are described here. Methods and techniques used at the Klet NEO follow-up CCD astrometric programme, using 1.06-m and 0.57-m telescopes, are also discussed.

Discovery of new changing look in NGC 1566

2019 ◽  
Vol 15 (S356) ◽  
pp. 127-131
Author(s):  
Victor L. Oknyansky ◽  
Sergey S. Tsygankov ◽  
Vladimir M. Lipunov ◽  
Evgeny S. Gorbovskoy ◽  
Nataly V. Tyurina
Keyword(s):  
South African ◽  
Astronomical Observatory ◽  
Emission Lines ◽  
Optical Monitoring ◽  
X Ray ◽  
Broad Emission ◽  
High Ionization ◽  
The Galaxy ◽  
Multi Wavelength ◽  
Bright Phase

AbstractWe present continuation of the multi-wavelength (from X-ray to optical) monitoring of the nearby changing look (CL) active galactic nucleus in the galaxy NGC 1566 performed with the Neil Gehrels Swift Observatory,the MASTER Global Robotic Network over the period 2007–2019. We also present continuation of optical spectroscopy using the South African Astronomical Observatory 1.9-m telescope between Aug. 2018 and Mar. 2019. We investigate remarkable re-brightenings in of the light curve following the decline from the bright phase observed at Dec. 2018 and at the end of May 2019. For the last optical spectra (31 Nov. 2018–28 Mar. 2019) we see dramatic changes compared to 2 Aug. 2018, accompanied by the fading of broad emission lines and high-ionization [FeX]6374Å line. Effectively, one more CL was observed for this object: changing from Sy1.2 to the low state as Sy 1.8–Sy1.9 type. Some possible explanations of the observed CL are discussed.

scholarly journals The XXL Survey

2020 ◽  
Vol 642 ◽  
pp. A126 ◽  
Author(s):  
M. Ricci ◽  
R. Adam ◽  
D. Eckert ◽  
P. Ade ◽  
P. André ◽  
...  
Keyword(s):  
High Redshift ◽  
High Mass ◽  
Optical Data ◽  
Local Pressure ◽  
Mass System ◽  
Cluster Galaxy ◽  
X Ray ◽  
The Galaxy ◽  
Low Mass ◽  
The Impact

High-mass clusters at low redshifts have been intensively studied at various wavelengths. However, while more distant objects at lower masses constitute the bulk population of future surveys, their physical state remain poorly explored to date. In this paper, we present resolved observations of the Sunyaev-Zel’dovich (SZ) effect, obtained with the NIKA2 camera, towards the cluster of galaxies XLSSC 102, a relatively low-mass system (M500 ∼ 2 × 1014 M⊙) at z = 0.97 detected from the XXL survey. We combine NIKA2 SZ data, XMM-Newton X-ray data, and Megacam optical data to explore, respectively, the spatial distribution of the gas electron pressure, the gas density, and the galaxies themselves. We find significant offsets between the X-ray peak, the SZ peak, the brightest cluster galaxy, and the peak of galaxy density. Additionally, the galaxy distribution and the gas present elongated morphologies. This is interpreted as the sign of a recent major merging event, which induced a local boost of the gas pressure towards the north of XLSSC 102 and stripped the gas out of the galaxy group. The NIKA2 data are also combined with XXL data to construct the thermodynamic profiles of XLSSC 102, obtaining relatively tight constraints up to about ∼r500, and revealing properties that are typical of disturbed systems. We also explore the impact of the cluster centre definition and the implication of local pressure substructure on the recovered profiles. Finally, we derive the global properties of XLSSC 102 and compare them to those of high-mass-and-low-redshift systems, finding no strong evidence for non-standard evolution. We also use scaling relations to obtain alternative mass estimates from our profiles. The variation between these different mass estimates reflects the difficulty to accurately measure the mass of low-mass clusters at z ∼ 1, especially with low signal-to-noise ratio data and for a disturbed system. However, it also highlights the strength of resolved SZ observations alone and in combination with survey-like X-ray data. This is promising for the study of high redshift clusters from the combination of eROSITA and high resolution SZ instruments and will complement the new generation of optical surveys from facilities such as LSST and Euclid.

scholarly journals Toward a characterization of X-ray galaxy clusters for cosmology

2019 ◽  
Vol 628 ◽  
pp. A43 ◽  
Author(s):  
Florian Käfer ◽  
Alexis Finoguenov ◽  
Dominique Eckert ◽  
Jeremy S. Sanders ◽  
Thomas H. Reiprich ◽  
...  
Keyword(s):  
Galaxy Clusters ◽  
Surface Brightness ◽  
Emission Measure ◽  
Cosmological Parameters ◽  
Outer Part ◽  
Systematic Difference ◽  
Zero Bias ◽  
X Ray ◽  
The Galaxy ◽  
The Impact

Context. In the framework of the hierarchical model the intra-cluster medium properties of galaxy clusters are tightly linked to structure formation, which makes X-ray surveys well suited for cosmological studies. To constrain cosmological parameters accurately by use of galaxy clusters in current and future X-ray surveys, a better understanding of selection effects related to the detection method of clusters is needed. Aims. We aim at a better understanding of the morphology of galaxy clusters to include corrections between the different core types and covariances with X-ray luminosities in selection functions. In particular, we stress the morphological deviations between a newly described surface brightness profile characterization and a commonly used single β-model. Methods. We investigated a novel approach to describe surface brightness profiles, where the excess cool-core emission in the centers of the galaxy clusters is modeled using wavelet decomposition. Morphological parameters and the residuals were compared to classical single β-models, fitted to the overall surface brightness profiles. Results. Using single β-models to describe the ensemble of overall surface brightness profiles leads on average to a non-zero bias (0.032 ± 0.003) in the outer part of the clusters, that is an approximate 3% systematic difference in the surface brightness at large radii. Furthermore, β-models show a general trend toward underestimating the flux in the outskirts for smaller core radii. Fixing the β parameter to 2/3 doubles the bias and increases the residuals from a single β-model up to more than 40%. Modeling the core region in the fitting procedure reduces the impact of these two effects significantly. In addition, we find a positive scaling between shape parameters and temperature, as well as a negative correlation of approximately −0.4 between extent and luminosity. Conclusion. We demonstrate the caveats in modeling galaxy clusters with single β-models and recommend using them with caution, especially when the systematics are not taken into account. Our non-parametric analysis of the self-similar scaled emission measure profiles indicates no systematic core-type differences of median profiles in the galaxy cluster outskirts.

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