Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations ...associated with the binary black hole (BBH) central engine of blazar OJ 287 demand the inclusion of gravitational radiation reaction effects beyond the quadrupolar order. It turns out that even the effects of certain hereditary contributions to GW emission are required to predict impact flare timings of OJ 287. We develop an approach that incorporates this effect into the BBH model for OJ 287. This allows us to demonstrate an excellent agreement between the observed impact flare timings and those predicted from ten orbital cycles of the BBH central engine model. The deduced rate of orbital period decay is nine orders of magnitude higher than the observed rate in PSR 1913+16, demonstrating again the relativistic nature of OJ 287's central engine. Finally, we argue that precise timing of the predicted 2019 impact flare should allow a test of the celebrated black hole "no-hair theorem" at the 10% level.
ABSTRACT OJ 287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts that are predictable in a binary black hole model. The model predicted a major optical ...outburst in 2015 December. We found that the outburst did occur within the expected time range, peaking on 2015 December 5 at magnitude 12.9 in the optical R-band. Based on Swift/XRT satellite measurements and optical polarization data, we find that it included a major thermal component. Its timing provides an accurate estimate for the spin of the primary black hole, . The present outburst also confirms the established general relativistic properties of the system such as the loss of orbital energy to gravitational radiation at the 2% accuracy level, and it opens up the possibility of testing the black hole no-hair theorem with 10% accuracy during the present decade.
We analyse the light curve in the R band of the blazar OJ287, gathered during the 2015/2016 observing season. We did a search for quasi-periodic oscillations (QPOs) using several methods over a wide ...range of timescales. No statistically significant periods were found in the high-frequency domain both in the ground-based data and in Kepler observations. In the longer-period domain, the Lomb-Scargle periodogram revealed several peaks above the 99% significance level. The longest one-about 95 days-corresponds to the innermost stable circular orbit (ISCO) period of the more massive black hole. The 43-day period could be an alias, or it can be attributed to accretion in the form of a two-armed spiral wave.
We present the results of our power spectral density analysis for the BL Lac object OJ 287, utilizing the Fermi-LAT survey at high-energy γ-rays, Swift-XRT in X-rays, several ground-based telescopes ...and the Kepler satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time autoregressive moving average (CARMA) processes. Owing to the inclusion of the Kepler data, we were able to construct for the first time the optical variability power spectrum of a blazar without any gaps across ∼6 dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the γ-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the Fermi-LAT data, corresponding to ∼150 days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise.
OJ287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts which are predictable in a binary black hole model. The model predicted a major optical outburst ...in December 2015. We found that the outburst did occur within the expected time range, peaking on 2015 December 5 at magnitude 12.9 in the optical R-band. Based on Swift/XRT satellite measurements and optical polarization data, we find that it included a major thermal component. Its timing provides an accurate estimate for the spin of the primary black hole, chi = 0.313 +- 0.01. The present outburst also confirms the established general relativistic properties of the system such as the loss of orbital energy to gravitational radiation at the 2 % accuracy level and it opens up the possibility of testing the black hole no-hair theorem with a 10 % accuracy during the present decade.
IntroductionPsychotic disorders have a huge impact on social functioning, which is the ability to stablish and maintain social activities such as interpersonal relationships and self-care activities ...of daily living. Research data support that the early intervention in people who have experienced a first episode of psychosis (FEP) -based on a multidisciplinary treatment including both psychopharmacological and psychosocial treatments-, has a relevant role in a favorable evolution. AGES-Mind study is based on manualized psychotherapeutic interventions for people with first-psychosis episodes.ObjectivesTo describe the use of rehabilitation resources and social functioning in a group of people with FEP who were included in a psychotherapeutic group program versus a control group, at 12 and 24 months since the beginning of the intervention.MethodsLongitudinal, analytical, observational, retrospective study on a cohort of 46 patients with first-episode psychosis within the last 5 years. 23 patients received group psychotherapy in the context of the AGES-Mind study and they were compared with 23 control patients who did not receive a group intervention (treatment as usual). Controls were matched by age, gender and time elapsed since the first episode of psychosis with those exposed to the intervention. Sociodemographic data, social functioning (self-care, social activities, social relationships, and behavior) and use of rehabilitation resources outcome variables were assessed.ResultsSignificant differences were found regarding participation in social activities in the intervention group versus control group at 24 months. No significant differences were found in other dimensions of social functioning or in the use of rehabilitation resources.Image:Image 2:ConclusionsFurther studies with larger sample sizes are needed in order to determine if the participation in group therapy leads to an improvement in social functioning and use of rehabilitation resources for people who have experienced a first episode of psychosis.Disclosure of InterestNone Declared
We present the results of our power spectral density analysis for the BL Lac object OJ\,287, utilizing the {\it Fermi}-LAT survey at high-energy \(\gamma\)-rays, {\it Swift}-XRT in X-rays, several ...ground-based telescopes and the {\it Kepler} satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time auto-regressive moving average (CARMA) processes. Owing to the inclusion of the {\it Kepler} data, we were able to construct \emph{for the first time} the optical variability power spectrum of a blazar without any gaps across \(\sim6\) dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the \(\gamma\)-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the {\it Fermi}-LAT data, corresponding to \(\sim 150\)\,days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise.
Sub‐nanometer metal clusters have special physical and chemical properties, significantly different from those of nanoparticles. However, there is a major concern about their thermal stability and ...susceptibility to oxidation. In situ X‐ray Absorption spectroscopy and Near Ambient Pressure X‐ray Photoelectron spectroscopy results reveal that supported Cu5 clusters are resistant to irreversible oxidation at least up to 773 K, even in the presence of 0.15 mbar of oxygen. These experimental findings can be formally described by a theoretical model which combines dispersion‐corrected DFT and first principles thermochemistry revealing that most of the adsorbed O2 molecules are transformed into superoxo and peroxo species by an interplay of collective charge transfer within the network of Cu atoms and large amplitude “breathing” motions. A chemical phase diagram for Cu oxidation states of the Cu5‐oxygen system is presented, clearly different from the already known bulk and nano‐structured chemistry of Cu.
A combined XANES and NAP XPS study shows that Cu5 clusters are resistant to irreversible oxidation up to 773 K in the presence of oxygen. A theoretical model reveals that adsorbed O2 molecules are transformed into superoxo and peroxo species by an interplay of collective charge transfer and large amplitude “breathing” motions. A chemical phase diagram for Cu oxidation state of the Cu5‐O2 system is presented.
Sub-nanometer metal clusters have special physical and chemical properties, significantly different from those of nanoparticles. However, there is a major concern about their thermal stability and ...susceptibility to oxidation. In situ X-ray Absorption spectroscopy and Near Ambient Pressure X-ray Photoelectron spectroscopy results reveal that supported Cu
clusters are resistant to irreversible oxidation at least up to 773 K, even in the presence of 0.15 mbar of oxygen. These experimental findings can be formally described by a theoretical model which combines dispersion-corrected DFT and first principles thermochemistry revealing that most of the adsorbed O
molecules are transformed into superoxo and peroxo species by an interplay of collective charge transfer within the network of Cu atoms and large amplitude "breathing" motions. A chemical phase diagram for Cu oxidation states of the Cu
-oxygen system is presented, clearly different from the already known bulk and nano-structured chemistry of Cu.
Bare clusters of five Cu atoms, synthesized electrochemically, display remarkable oxidation stability on highly oriented pyrolytic graphite. They exhibit reversible O2 adsorption, transitioning ...between various Cu oxidation states with changes in temperature and O2 pressure. In‐situ XPS and XANES spectroscopy experiments, along with theoretical characterizations of Cu5–(O2)n complexes, provide direct evidence of the Cu5 clusters’ O2 stability. More information can be found in the Research Article by M. P. de Lara‐Castells, F. G. Requejo, M. A. López‐Quintela and co‐workers (DOI: 10.1002/chem.202301517).
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