New determination of 12C(α,γ)16O reaction rate

2015 ◽  
Vol 24 (12) ◽  
pp. 1550098
Author(s):  
N. Oulebsir
Keyword(s):  
Reaction Rate ◽  
Transfer Reaction ◽  
Center Of Mass ◽  
Scattering Data ◽  
Center Of Mass Energy ◽  
Stellar Temperature ◽  
New Formula ◽  
Threshold Resonances ◽  
Astrophysical Reaction Rate

The reaction [Formula: see text]C([Formula: see text])[Formula: see text]O was investigated through the direct [Formula: see text]-transfer reaction (7Li,t) at 28 and 34 MeV incident energies. We determined the reduced [Formula: see text]-widths of the sub-threshold 2[Formula: see text] and 1[Formula: see text] states of [Formula: see text]O from the DWBA analysis of the transfer reaction [Formula: see text]C(7Li,t)[Formula: see text]O performed at two incident energies. The obtained result for the 2[Formula: see text] and 1[Formula: see text] sub-threshold resonances as introduced in the [Formula: see text]-matrix fitting of radiative capture and elastic-scattering data to determine the E2 and E1 [Formula: see text]-factor from 0.01[Formula: see text]MeV to 4.2[Formula: see text]MeV in the center-of-mass energy. After determining the astrophysic factor of [Formula: see text]C([Formula: see text])[Formula: see text]O S(E) with Pierre Descouvement code, I determined numerically the new reaction rate of this reaction at a different stellar temperature (0.06 Gk-2 GK). The [Formula: see text]C([Formula: see text])[Formula: see text]O reaction rate at T[Formula: see text] is [7.21[Formula: see text]] × 10[Formula: see text] cm3 s[Formula: see text] mol[Formula: see text]. Some comparisons and discussions about our new [Formula: see text]C([Formula: see text])[Formula: see text]O reaction rate are presented. The agreements of the reaction rate below T[Formula: see text] between our results and with those proposed by NACRE indicate that our results are reliable, and they could be included in the astrophysical reaction rate network.

scholarly journals Measuring the quartic Higgs self-coupling at a multi-TeV muon collider

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
M. Chiesa ◽  
F. Maltoni ◽  
L. Mantani ◽  
B. Mele ◽  
F. Piccinini ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Center Of Mass ◽  
Mass Energy ◽  
Simple Analysis ◽  
Proton Proton ◽  
Coupling Interaction ◽  
Center Of Mass Energy ◽  
Muon Collider ◽  
Better Than

Abstract Measuring the shape of the Higgs boson potential is of paramount importance, and will be a challenging task at current as well as future colliders. While the expectations for the measurement of the trilinear Higgs self-coupling are rather promising, an accurate measurement of the quartic self-coupling interaction is presently considered extremely challenging even at a future 100 TeV proton-proton collider. In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background. By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders.

scholarly journals FRAGMENTATION FUNCTIONS AT BABAR

2014 ◽  
Vol 25 ◽  
pp. 1460044
Author(s):  
◽  
ISABELLA GARZIA
Keyword(s):  
Charged Pion ◽  
Production Cross ◽  
Center Of Mass ◽  
Center Of Mass Energy ◽  
Charged Pions ◽  
Fragmentation Functions ◽  
Fragmentation Processes ◽  
Azimuthal Modulation ◽  
Shed Light

Inclusive hadron production cross section in e+e- annihilation shed light on fundamental questions of hadronization and fragmentation processes. We present measurements of inclusive spectra of charged pions, kaons, and protons (antiprotons) produced in e+e- collisions at the center-of-mass energy of 10.54 GeV, and tests of QCD predictions and hadronization models. We also report the results on the measurement of the azimuthal modulation induced by the Collins effect in inclusive production of charged pion pairs e+e- → ππX, where the two pions are produced in opposite hemispheres. These data allows the determination of the polarized Collins fragmentation functions.

Determination of the proton-proton elastic cross section at 30 GeV center of mass energy

1971 ◽  
Vol 35 (4) ◽  
pp. 361-364 ◽  
Author(s):  
M. Holder ◽  
E. Radermacher ◽  
A. Staude ◽  
G. Barbiellini ◽  
P. Darriulat ◽  
...  
Keyword(s):  
Cross Section ◽  
Center Of Mass ◽  
Elastic Cross Section ◽  
Mass Energy ◽  
Proton Proton ◽  
Center Of Mass Energy

scholarly journals Constraining capability of Zγh production at the ILC

2017 ◽  
Vol 32 (02n03) ◽  
pp. 1750017
Author(s):  
Sher Alam ◽  
Subhasish Behera ◽  
Satendra Kumar ◽  
Shibananda Sahoo
Keyword(s):  
Higgs Boson ◽  
Center Of Mass ◽  
Beam Polarization ◽  
Mass Energy ◽  
Gauge Bosons ◽  
Center Of Mass Energy ◽  
Lagrangian Framework ◽  
Effective Lagrangian ◽  
Coupling Parameters

Higgs boson couplings with gauge bosons are probed through [Formula: see text] in an effective Lagrangian framework. For this study, the beam polarization facility at the ILC along with the typical center-of-mass energy of 500 GeV is considered. The reach of the ILC with an integrated luminosity of 300 fb[Formula: see text] in the determination of CP-conserving parameters is obtained. Sensitivity of the probe of each of these couplings in the presence of other couplings is investigated. The most influential coupling parameters are [Formula: see text]. Other parameters of significant effect are [Formula: see text] and [Formula: see text]. A detailed study of the various kinematic distributions represents possibilities to disentangle the effect of some of these couplings.

Exploring Baryon Rich Matter with Heavy-Ion Collisions

2019 ◽  
Vol 64 (7) ◽  
pp. 583 ◽  
Author(s):  
S. Harabasz
Keyword(s):  
Center Of Mass ◽  
Heavy Ion ◽  
State Density ◽  
Heavy Nuclei ◽  
First Order ◽  
Center Of Mass Energy ◽  
Ion Collisions ◽  
Deconfinement Phase Transition ◽  
Ground State Density

Collisions of heavy nuclei at (ultra-)relativistic energies provide a fascinating opportunity to re-create various forms of matter in the laboratory. For a short extent of time (10-22 s), matter under extreme conditions of temperature and density can exist. In dedicated experiments, one explores the microscopic structure of strongly interacting matter and its phase diagram. In heavy-ion reactions at SIS18 collision energies, matter is substantially compressed (2–3 times ground-state density), while moderate temperatures are reached (T < 70 MeV). The conditions closely resemble those that prevail, e.g., in neutron star mergers. Matter under such conditions is currently being studied at the High Acceptance DiElecton Spectrometer (HADES). Important topics of the research program are the mechanisms of strangeness production, the emissivity of matter, and the role of baryonic resonances herein. In this contribution, we will focus on the important experimental results obtained by HADES in Au+Au collisions at 2.4 GeV center-of-mass energy. We will also present perspectives for future experiments with HADES and CBM at SIS100, where higher beam energies and intensities will allow for the studies of the first-order deconfinement phase transition and its critical endpoint.

Alcohol Determination by HPLC with Postcolumn Derivatization Based on the Thiosulfate-catalyzed Reaction of Alcohols and Cerium(IV) and Fluorescence Detection of Cerium(III)

2020 ◽  
Vol 16 ◽  
Author(s):  
Ikko Mikami ◽  
Eri Shibayama ◽  
Kengo Takagi
Keyword(s):  
Detection Limit ◽  
Fluorescence Detection ◽  
Reaction Rate ◽  
Detection Method ◽  
Fluorescence Detector ◽  
Reaction Solution ◽  
Optimum Detection ◽  
Postcolumn Derivatization ◽  
Sensitive Method

Background: Determination of a reducing substance based on the reaction between Ce(IV) and a reducing substance and fluorescence detection of Ce(III) generated has been reported as a selective and sensitive method. However, this method could not be applied to the determination of alcohol due to the low reaction rate of alcohol and Ce(IV). Objective: We found that thiosulfate catalytically enhanced reaction of alcohols (such as, methanol, ethanol, and propanol) and Ce(IV). Utilizing this effect, we developed a new method for the determination of alcohols. Results: In the presence of thiosulfate, an increase in fluorescence intensity was detected by injecting alcohol at concentrations of several millimolar, whereas it was not observed even at the concentration of 10% v/v (2 M for ethanol) in the absence of thiosulfate. The optimum detection conditions were determined to be 4.0 mM Ce(IV) sulfate and 0.50 mM thiosulfate, and the detection limit (S/N = 3) of ethanol under these conditions was 1 mM. In the calibration curves, changes in the slope were observed when the alcohol concentrations were approximately 10–25 mM. Using a thiosulfate solution containing ethanol as the reaction solution, a calibration curve without any change in slope was obtained, although the concentration of ethanol at the detection limit increased. The alcohols in the liquor and fuel were successfully analyzed using the proposed detection method as a postcolumn reaction. Conclusion: This new alcohol detection method using a versatile fluorescence detector can be applied to the postcolumn reaction of HPLC omitting need of time-consuming pretreatment processes.

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