THE SEARCH FOR THE DECAY OF Z BOSON INTO TWO PHOTONS AS A TEST OF BOSE STATISTICS

The dependence of the dynamic range of the phase generated carrier (PGC) technique on low-pass filters passbands is investigated using a simulation model. A nonlinear character of this dependence, which could lead to dynamic range limitations or measurement uncertainty, is presented for the first time. A detailed theoretical analysis is provided to verify the simulation results and these results are consistent with performed calculations. The method for the calculation of low-pass filters passbands according to the required dynamic range upper limit is proposed.

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Long term Arecibo monitoring of the water megamaser in MG J0414+0534

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312007272 ◽

2012 ◽

Vol 8 (S287) ◽

pp. 340-344

Author(s):

Paola Castangia ◽

C. M. Violette Impellizzeri ◽

John P. McKean ◽

Christian Henkel ◽

Andreas Brunthaler ◽

...

Keyword(s):

High Redshift ◽

Main Peak ◽

Powerful Radio ◽

Upper Limit ◽

Maser Line ◽

Line Widths ◽

Velocity Drift ◽

First Time ◽

Water Maser

AbstractWe monitored the 22 GHz maser line in the lensed quasar MG J0414+0534 at z = 2.64 with the 300-m Arecibo telescope for almost two years to detect possible additional maser components and to measure a potential velocity drift of the lines. The main maser line profile is complex and can be resolved into a number of broad features with line widths of 30-160 km s−1. A new maser component was tentatively detected in October 2008 at a velocity of +470 km s−1. After correcting for the estimated lens magnification, we find that the H2O isotropic luminosity of the maser in MG J0414+0534 is ~26,000 solar luminosities, making this source the most luminous ever discovered. Both the main line peak and continuum flux densities are surprisingly stable throughout the period of the observations. An upper limit on the velocity drift of the main peak of the line has been estimated from our observations and is of the order of 2 km s−1 per year. We discuss the results of the monitoring in terms of the possible nature of the maser emission, associated with an accretion disk or a radio jet. This is the first time that such a study is performed in a water maser source at high redshift, potentially allowing us to study the parsec-scale environment around a powerful radio source at cosmological distances.

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Probing the physical and mathematical structure of f(R)-gravity by PSR J0348 + 0432

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887815500401 ◽

2015 ◽

Vol 12 (04) ◽

pp. 1550040 ◽

Cited By ~ 16

Author(s):

Mariafelicia De Laurentis ◽

Ivan De Martino

Keyword(s):

General Relativity ◽

Binary Systems ◽

Time Derivative ◽

Mathematical Structure ◽

Graviton Mass ◽

Upper Limit ◽

Extended Theories Of Gravity ◽

Theories Of Gravity ◽

First Time ◽

Extended Theories

There are several approaches to extend General Relativity in order to explain the phenomena related to the Dark Matter and Dark Energy. These theories, generally called Extended Theories of Gravity, can be tested using observations coming from relativistic binary systems as PSR J0348 + 0432. Using a class of analytical f(R)-theories, one can construct the first time derivative of orbital period of the binary systems starting from a quadrupolar gravitational emission. Our aim is to set boundaries on the parameters of the theory in order to understand if they are ruled out, or not, by the observations on PSR J0348 + 0432. Finally, we have computed an upper limit on the graviton mass showing that agree with constraint coming from other observations.

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Use of community-based indices to monitor eutrophication in European rivers

Environmental Conservation ◽

10.1017/s037689299800006x ◽

1998 ◽

Vol 25 (1) ◽

pp. 22-29 ◽

Cited By ~ 29

Author(s):

MARTYN G. KELLY

Keyword(s):

Organic Pollution ◽

Theoretical Framework ◽

Community Based ◽

Ecological Response ◽

Upper Limit ◽

Diatom Communities ◽

The Uk ◽

First Time

New legislation has encouraged regulatory biologists in the UK to examine the impacts of eutrophication in rivers for the first time. The principal tools for this have been new indices based on macrophyte and diatom communities. The use of such indices is placed within an appropriate theoretical framework. The importance of recognizing the upper limit of sensitivity of such indices, as well as factors such as organic pollution, which can confuse interpretation, is discussed. Despite their limitations, community-based indices are valuable tools for reconnaissance studies and, in the long-term, as indicators of the extent to which nutrient reductions have led to an ecological response. Some general guidelines for monitoring eutrophication in rivers are proposed.

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Ladislas Natanson and Alfred Landé versus Planck’s law, the Boltzmann-Planck-Natanson statistics and the Bose statistics

Studia Historiae Scientiarum ◽

10.4467/2543702xshs.21.014.14045 ◽

2021 ◽

Vol 20 ◽

pp. 439-507

Author(s):

Michał Kokowski

Keyword(s):

Bose Statistics ◽

Planck’S Law ◽

First Time

The article describes the context and content of the November 1925 correspondence – so far overlooked by historians of physics – between Władysław (Ladislas) Natanson and Alfred Landé on Planck’s law and Bose statistics, and the effects of this interaction. The article publishes for the first time the transcription of two original letters in German and their translations into English.

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Object-based Verification of Atmospheric River Predictions in the Northeast Pacific

Weather and Forecasting ◽

10.1175/waf-d-20-0236.1 ◽

2021 ◽

Author(s):

Laurel L. DeHaan ◽

Andrew C. Martin ◽

Rachel R. Weihs ◽

Luca Delle Monache ◽

F. Martin Ralph

Keyword(s):

Weather Prediction ◽

Quantitative Measure ◽

Cold Season ◽

Forecast Skill ◽

Atmospheric Rivers ◽

Landslide Hazards ◽

Object Based ◽

Evaluation Mode ◽

First Time ◽

Effective Water

AbstractAccurate forecasts of atmospheric rivers (ARs) provide advance warning of flood and landslide hazards, as well as greatly aid effective water management. It is therefore critical to evaluate the skill of AR forecasts in numerical weather prediction (NWP) models. A new verification framework is proposed leveraging freely available software and metrics previously used for different applications. Specifically, AR detection and statistics are computed for the first time using the Method for Object-based Diagnostic Evaluation (MODE). In addition, the measure of effectiveness (MoE) is introduced as a new metric for understanding AR forecast skill in terms of size and location. The MoE provides a quantitative measure of the position of an entire forecasted AR compared to observation, regardless of whether the AR is making landfall. In addition, the MoE can provide qualitative information about the evolution of a forecast by lead time with implications about the predictability of an AR. We analyze AR forecast verification and skill using 11 years of cold season forecasts from two NWP models, one global and one regional. Four different thresholds of integrated vapor transport (IVT) are used in the verification revealing differences in forecast skill based on the strength of an AR. In addition to MoE, AR forecast skill is also addressed in terms of intensity error, landfall position error, and contingency table metrics.

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Tomographic images of Avacha and Koryaksky volcanoes in Kamchatka

10.5194/egusphere-egu2020-4539 ◽

2020 ◽

Author(s):

Natalia Bushenkova ◽

Ivan Koulakov ◽

Sergey Senyukov ◽

Evgeny I. Gordeev ◽

Hsin-Hua Huang ◽

...

Keyword(s):

3D Structure ◽

Thick Layer ◽

Potential Hazard ◽

Tomographic Images ◽

Arrival Times ◽

S Waves ◽

Partial Melt ◽

Magma Reservoirs ◽

Upper Limit ◽

First Time

In this study, we have mapped for the first time robustly the 3D structure of two upper-crustal magmatic reservoirs beneath the active volcanoes Avacha and Koryaksky, which are called &#8220;home volcanoes&#8221; for Petropavlovsk-Kamchatsky, the main city of Kamchatka (~200,000 inhabitants). These volcanoes represent a serious potential hazard for the city, because they are located at a distance of 25&#8211;30 km from the populated areas. A new tomographic model (VP, VS, VP/VS ratio) was built, for which we used the arrival times of seismic P- and S-waves from almost 5,000 local events, recorded by a permanent network of seismic stations during 2009&#8211;2018.The resolution of the derived models was carefully tested by a series of synthetic simulations. Prominent anomalies with extremely high VP/VS ratios (up to 2.4) were retrieved directly beneath both volcanoes and interpreted as magma reservoirs containing high degrees of partial melt and/or fluids. Beneath Avacha, the upper limit of the anomaly is located at the depth of ~2 km below the surface. The reservoir appears to be connected to the surface by a neck-shaped anomaly of high VP/VS ratio associated with active seismicity, which is interpreted as a magma and fluid conduit. Beneath Koryaksky, the magma related anomaly is deeper: its upper limit is located at a depth of ~ 7 km below the surface. This anomaly is connected with the volcanic coneby a vertical seismicity cluster, which possibly marks the pathway of fluid ascent and degassing. Between the volcanoes, a 2&#8211;3 km thick layer of very low VP and VS is interpreted as deposits of volcanoclastic sediments. Generally low Vp/Vs ratios in the area between the volcanoes show that the magma reservoirs in the upper crust are not interconnected.This study was partially supported by the RFBR project # 18-55-52003.

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Study of Drell-Yan dimuon production in proton-lead collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ = 8.16 TeV

Journal of High Energy Physics ◽

10.1007/jhep05(2021)182 ◽

2021 ◽

Vol 2021 (5) ◽

Author(s):

A. M. Sirunyan ◽

◽

A. Tumasyan ◽

W. Adam ◽

F. Ambrogi ◽

...

Keyword(s):

Cross Sections ◽

Differential Cross ◽

Z Boson ◽

Decay Channel ◽

Nucleon Nucleon ◽

Mass Region ◽

Differential Cross Sections ◽

Dimuon Production ◽

Rapidity Dependence ◽

First Time

Abstract Differential cross sections for the Drell-Yan process, including Z boson production, using the dimuon decay channel are measured in proton-lead (pPb) collisions at a nucleon-nucleon centre-of-mass energy of 8.16 TeV. A data sample recorded with the CMS detector at the LHC is used, corresponding to an integrated luminosity of 173 nb−1. The differential cross section as a function of the dimuon mass is measured in the range 15–600 GeV, for the first time in proton-nucleus collisions. It is also reported as a function of dimuon rapidity over the mass ranges 15–60 GeV and 60–120 GeV, and ratios for the p-going over the Pb-going beam directions are built. In both mass ranges, the differential cross sections as functions of the dimuon transverse momentum pT and of a geometric variable ϕ* are measured, where ϕ* highly correlates with pT but is determined with higher precision. In the Z mass region, the rapidity dependence of the data indicate a modification of the distribution of partons within a lead nucleus as compared to the proton case. The data are more precise than predictions based upon current models of parton distributions.

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SILVERRUSH. XI. Constraints on the Lyα Luminosity Function and Cosmic Reionization at z = 7.3 with Subaru/Hyper Suprime-Cam

The Astrophysical Journal ◽

10.3847/1538-4357/ac308b ◽

2021 ◽

Vol 923 (2) ◽

pp. 229

Author(s):

Hinako Goto ◽

Kazuhiro Shimasaku ◽

Satoshi Yamanaka ◽

Rieko Momose ◽

Makoto Ando ◽

...

Keyword(s):

Luminosity Function ◽

Intergalactic Medium ◽

Neutral Hydrogen ◽

Neutral Fraction ◽

Estimation Methods ◽

Large Area ◽

Upper Limit ◽

Narrowband Imaging ◽

First Time

Abstract The Lyα luminosity function (LF) of Lyα emitters (LAEs) has been used to constrain the neutral hydrogen fraction in the intergalactic medium (IGM) and thus the timeline of cosmic reionization. Here we present the results of a new narrowband imaging survey for z = 7.3 LAEs in a large area of ∼3 deg2 with Subaru/Hyper Suprime-Cam. No LAEs are detected down to L Lyα ≃ 1043.2 erg s−1 in an effective cosmic volume of ∼2 × 106 Mpc3, placing an upper limit on the bright part of the z = 7.3 Lyα LF for the first time and confirming a decrease in bright LAEs from z = 7.0. By comparing this upper limit with the Lyα LF in the case of fully ionized IGM, which is predicted using an observed z = 5.7 Lyα LF on the assumption that the intrinsic Lyα LF evolves in the same way as the UV LF, we obtain the relative IGM transmission T Ly α IGM ( 7.3 ) / T Ly α IGM ( 5.7 ) < 0.77 and then the volume-averaged neutral fraction x H I(7.3) > 0.28. Cosmic reionization is thus still ongoing at z = 7.3, consistent with results from other x H I estimation methods. A similar analysis using literature Lyα LFs finds that at z = 6.6 and 7.0, the observed Lyα LF agrees with the predicted one, consistent with full ionization.

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Question on Diphenylhydantoin Dosage

PEDIATRICS ◽

10.1542/peds.55.6.897a ◽

1975 ◽

Vol 55 (6) ◽

pp. 897-897

Author(s):

Irwin L. Schwartz

Keyword(s):

Blood Levels ◽

High Dose ◽

Upper Limit ◽

High Doses ◽

Psychomotor Epilepsy ◽

First Time

I note in the article "Psychomotor Epilepsy," which appeared in Pediatrics, that Dr. Gold recommends a dosage of 10 mg/kg of diphenylhydantoin (Dilantin). He states that "when phenobarbital is not tolerated or seizures are not controlled," the diphenylhydantoin should be added or substituted. This is the first time I have ever seen such a high dose recommended, the usual upper limit recommended in most textbooks being 7 or 8 mg/kg. Would you please reply to this in view of the fact that high doses may yield high blood levels which could be toxic to the liver.

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