Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b

We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society

Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run

Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society

Search for gravitational-wave transients associated with magnetar bursts in advanced LIGO and advanced Virgo data from the third observing run

Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant f lares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and longduration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA’s third observation run. These 13 bursts come from two magnetars, SGR1935 +2154 and SwiftJ1818.0−1607. We also include three other electromagnetic burst events detected by FermiGBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant flares were detected during the analysis period. We find no evidence of gravitational waves associated with any of these 16 bursts. We place upper limits on the rms of the integrated incident gravitational-wave strain that reach 3.6 × 10−²³ Hz at 100 Hz for the short-duration search and 1.1 ×10−²² Hz at 450 Hz for the long-duration search. For a ringdown signal at 1590 Hz targeted by the short-duration search the limit is set to 2.3 × 10−²² Hz. Using the estimated distance to each magnetar, we derive upper limits upper limits on the emitted gravitational-wave energy of 1.5 × 1044 erg (1.0 × 1044 erg) for SGR 1935+2154 and 9.4 × 10^43 erg (1.3 × 1044 erg) for Swift J1818.0−1607, for the short-duration (long-duration) search. Assuming isotropic emission of electromagnetic radiation of the burst fluences, we constrain the ratio of gravitational-wave energy to electromagnetic energy for bursts from SGR 1935+2154 with the available fluence information. The lowest of these ratios is 4.5 × 103

A joint Fermi-GBM and Swift-BAT analysis of gravitational-wave candidates from the third gravitational-wave observing run

We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers

Constraints on the cosmic expansion history from GWTC–3

We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding ${H}_{0}={68}_{-8}^{+12}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ (68% credible interval) when combined with the H0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event's potential hosts. Assuming a fixed BBH population, we estimate a value of ${H}_{0}={68}_{-6}^{+8}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H0) is the well-localized event GW190814

α-cardiac Actin (actc) Binds To The Band 3 (ae1) Cardiac Isoform

The band 3 protein is the major integral protein present in the erythrocyte membrane. Two tissue-specific isoforms are also expressed in kidney alpha intercalated cells and in cardiomyocytes. It has been suggested that the cardiac isoform predominantly mediates the anion exchange in cardiomyocytes, but the role of the cytoplasmic domain of the band 3 (CDB3) protein in the cardiac tissue is unknown. In order to characterize novel associations of the CDB3 in the cardiac tissue, we performed the two-hybrid assay, using a bait comprising the region from leu 258 to leu 311 of the erythrocyte band 3, which must also be present in the cardiac isoform. The assay revealed two clones containing the C-terminal region of the α-cardiac actin. Immunoprecipitation of whole rat heart using an anti-actin antibody, immunoblotted with anti-human band 3, showed that actin binds to band 3 which was confirmed in the reverse assay. The confocal microscopy showed band 3 in the intercalated discs. Thus, besides the in vivo physical interaction in the Saccharomyces cerevisiae cell, we demonstrated using immunopreciptation that there is a physical association of band 3 with α-cardiac actin in cardiomyocyte, and we suggest that the binding occur "in situ," in the intercalated disc, a site of cell-cell contact and attachment of the sarcomere to the plasma membrane. © 2003 Wiley-Liss, Inc.89612151221Aho, S., Arffman, A., Pummi, T., Uitto, J., A novel reporter gene MEL 1 for the yeast two-hybrid system (1997) Anal Biochem, 253, pp. 270-272Batrukova, M.A., Betin, V.L., Rubtsov, A.M., Lopina, O.D., Ankyrin: Structure, properties, and functions (2000) Biochemistry, 65, pp. 395-408Clark, K.A., McElhinny, A.S., Beckerle, M.C., Gregorio, C.C., Striated muscle cytoarchitecture: An intricate web of form and function (2002) Annu Rev Cell Dev Biol, 18, pp. 637-706Fairbanks, V.F., Steck, T.L., Wallach, D.F.H., Electrophoretic analysis of the human erythrocyte membrane (1971) Biochemistry, 10, pp. 2606-2614Fatkin, D., Graham, R.M., Molecular mechanisms of inherited cardiomyopathies (2002) Physiol Rev, 82, pp. 945-980Gietz, D., St. Jean, A., Woods, R.A., Schiesti, R.H., Improved method for higher-efficiency transformation of intact cells (1992) Nucleic Acids Res, 20, p. 1425Gregorio, C.C., Models of thin filament assembly in cardiac and skeletal muscle (1997) Cell Struct Funct, 22, pp. 191-195Harrison, M.L., Rathinavelu, P., Arese, P., Geahlen, R.L., Low, P.S., Role of the band 3 tyrosine phosphorylation in the regulation of erythrocyte glycolysis (1991) J Biol Chem, 266, pp. 4106-4111Harrison, M.L., Isaacson, C.C., Burg, D.L., Geahlen, R.L., Low, P.S., Phosphorylation of the human erythrocyte band 3 by endogenous p72syk (1994) J Biol Chem, 269, pp. 955-959Hill, J., Donald, K.A., Griffiths, D.E., DMSO-enhanced whole cell yeast transformation (1991) Nucleic Acids Res, 19, p. 5791Ito, H., Fukuda, Y., Murata, K., Kimura, A., Transformation of intact yeast cells treated with alkali cations (1983) J Bacteriol, 153, pp. 163-168James, P., Haliaday, J., Craig, E.A., Genomic libraries and a host strain designed for highly efficient two-hybrid selection in yeast (1996) Genetics, 144, pp. 1425-1436Kabsch, W., Mannherz, H.G., Suck, D., Pai, E.F., Holmes, K.C., Atomic structure of the actin: DNase I complex (1990) Nature, 347, pp. 37-44Korichneva, I., Puceat, M., Cassoly, R., Vassort, G., Cl-HCO3-exchange in developing neonatal rat cardiac cells. Biochemical identification and immunolocalization of band 3-like proteins (1995) Circ Res, 77, pp. 556-564Kudrycki, K.E., Schull, G.E., Rat kidney band 3 Cl -/HCO 3 - exchanger mRNA is transcribed from an alternative promoter (1993) Am J Physiol, 264, pp. F540-F547Low, P.S., Structure and function of cytoplasmic domain of band 3: Center of erythrocyte membrane-peripheral protein interactions (1986) Biochim Biophys Acta, 846, pp. 145-167Lu, M.H., DiLullo, C., Schultheiss, T., Holtzer, S., Murray, J.M., Choi, J., Fischman, D.A., Holtzer, H., The vinculin/sarcomeric-alpha-actinin/alpha-actin nexus in cultured cardiac myocytes (1992) J Cell Biol, 117, pp. 1007-1022Mogensen, J., Klausen, I.C., Pedersen, A.K., Egeblad, H., Bross, P., Kruse, T.A., Gregersen, N., Borglum, A.D., Alpha-cardiac actin is a novel disease gene in familial hypertrophic cardiomyopathy (1999) J Clin Invest, 103, pp. R39-R43Olson, T.M., Michels, W., Thibodeau, S.N., Tai, Y.S., Keating, M.T., Actin mutations in dilated cardiomyopathy, a heritable form of heart failure (1998) Science, 280, pp. 750-752Olson, T.M., Doan, T.P., Kishimoto, N.Y., Whitby, F.G., Ackerman, M.J., Fananapazir, L., Inherited and de novo mutations in the cardiac actin gene cause hypertrophic cardiomyopathy (2000) J Mol Cell Cardiol, 32, pp. 1687-1694Pawloski, J.R., Hess, D.T., Stamler, J.S., Export by red blood cells of nitric oxide bioactivity (2001) Nature, 409, pp. 622-626Richards, S.M., Jaconi, M.E., Vassort, G., Puceat, M., A spliced variant of AE1 gene encodes a truncated form of band 3 in heart: The predominant anion exchanger in ventricular myocytes (1999) J Cell Sci, 112, pp. 1519-1528Rybicki, A.C., Musto, S., Schwartz, R.S., Identification of a band-3 binding site near the N-terminus of erythrocyte membrane protein 4.2 (1995) Biochem J, 309, pp. 677-681Salhany, J.M., (1990) Erythrocyte Band 3 Protein, , Boca Raton, FL: CRC PressSchiestl, R.H., Gietz, R.D., High-efficiency transformation of intact cells using single-stranded nucleic acids as a carrier (1989) Curr Genet, 16, pp. 339-346Vince, J.W., Reithmeier, R.A.F., Identification of the carbonic anhydrase II binding site in the Cl/HCO 3 anion exchanger AE1 (2000) Biochemistry, 39, pp. 5527-5533Volk, T., Geiger, B., A-CAM: A 135-kDa receptor of intercellular adherens junctions. II. Antibody-mediated modulation of junction formation (1986) J Cell Biol, 103, pp. 1451-1464Von Ruckmann, B., Jons, T., Dolle, F., Drenckhahn, D., Schubert, D., Cytoskeleton-membrane connections in the human erythrocyte membrane: Band 4.1 binds to tetrameric band 3 protein (1997) Biochim Biophys Acta, 1325, pp. 226-234Zhang, D., Kiyatkin, A., Bolin, J.T., Low, P.S., Crystallographic structure and functional interpretation of the cytoplasmic domain of erythrocyte membrane band 3 (2000) Blood, 96, pp. 2925-293