arXiv subjects

V. Glagolev

Publications and source records attributed to V. Glagolev.

44 records · Page 3Linked to original sources

arXiv2015

Evidence of Cluster Structure of $^9$Be from $^3$He+$^9$Be Reaction

The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a $^{9}$Be target with a $^3$He beam at an incident energy of 30 MeV. Angular distributions for $^9$Be($^3$He,$^3$He)$^{9}$Be, $^9$Be($^3$He,$^4$He)$^{8}$Be, $^9$Be($^3$He,$^5$He)$^{7}$Be, $^9$Be($^3$He,$^6$Li)$^6$Li and $^9$Be($^3$He,$^5$Li)$^7$Li reaction channels were measured. Experimental angular distributions for the corresponding ground states (g.s.) were analysed within the framework of the optical model, the coupled-channel approach and the distorted-wave Born approximation. Cross sections for channels leading to unbound $^5$He$_{g.s.}$, $^5$Li$_{g.s.}$ and $^8$Be systems were obtained from singles measurements where the relationship between the energy and the scattering angle of the observed stable ejectile is constrained by two-body kinematics. Information on the cluster structure of $^{9}$Be was obtained from the transfer channels. It was concluded that cluster transfer is an important mechanism in the investigated nuclear reactions. In the present work an attempt was made to estimate the relative strengths of the interesting $^8$Be+$n$ and $^5$He+$α$ cluster configurations in $^9$Be. The branching ratios have been determined confirming that the $^5$He+$α$ configuration plays an important role. The configuration of $^9$Be consisting of two bound helium clusters $^3$He+$^6$He is significantly suppressed, whereas the two-body configurations ${}^{8}$Be+$n$ and ${}^{5}$He+$α$ including unbound $^8$Be and $^5$He are found more probable.

nucl-ex↗

arXiv2013

Excitation of the Delta(1232) isobar in deuteron charge exchange on hydrogen at 1.6, 1.8, and 2.3 GeV

The charge-exchange break-up of polarised deuterons pol{d}p -> {pp}n, where the final {pp} diproton system has a very low excitation energy and hence is mainly in the 1S0 state, is a powerful tool to probe the spin-flip terms in the proton-neutron charge-exchange scattering. Recent measurements with the ANKE spectrometer at the COSY storage ring at 1.6, 1.8, and 2.27 GeV have extended these studies into the pion-production regime in order to investigate the mechanism for the excitation of the Delta(1232) isobar in the pol{d}p -> {pp}X reaction. Values of the differential cross section and two deuteron tensor analysing powers, A_{xx} and A_{yy}, have been extracted in terms of the momentum transfer to the diproton or the invariant mass Mx of the unobserved system X. The unpolarised cross section in the high Mx region is well described in a model that includes only direct excitation of the Delta isobar through undistorted one pion exchange. However, the cross section is grossly underestimated for low Mx, even when Delta excitation in the projectile deuteron is included in the calculation. Furthermore, direct Delta production through one pion exchange only reproduces the angular dependence of the difference between the two tensor analysing powers.

nucl-ex↗

arXiv2012

The neutron-proton charge-exchange amplitudes measured in the dp -> ppn reaction

The unpolarised differential cross section and the two deuteron tensor analysing powers A_{xx} and A_{yy} of the pol{d}p -> (pp)n charge-exchange reaction have been measured with the ANKE spectrometer at the COSY storage ring. Using deuteron beams with energies 1.2, 1.6, 1.8, and 2.27 GeV, data were obtained for small momentum transfers to a (pp) system with low excitation energy. The results at the three lower energies are consistent with impulse approximation predictions based upon the current knowledge of the neutron-proton amplitudes. However, at 2.27GeV, where these amplitudes are far more uncertain, agreement requires a reduction in the overall double-spin-flip contribution, with an especially significant effect in the longitudinal direction. These conclusions are supported by measurements of the deuteron-proton spin-correlation parameters C_{x,x} and C_{y,y} that were carried out in the pol{d}pol{p} -> (pp)n reaction at 1.2 and 2.27GeV. The values obtained for the proton analysing power also suggest the need for a radical re-evaluation of the neutron-proton elastic scattering amplitudes at the higher energy. It is therefore clear that such measurements can provide a valuable addition to the neutron-proton database in the charge-exchange region.

nucl-ex↗

arXiv2012

Mu2e Conceptual Design Report

Mu2e at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N --> e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the conceptual design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-1 approval, which was granted July 11, 2012.

physics.ins-det↗

arXiv2008

Neutron-proton charge-exchange amplitudes at 585 MeV

The differential cross section and deuteron analysing powers of the dp -> {pp}n charge-exchange reaction have been measured with the ANKE spectrometer at the COSY storage ring. Using a deuteron beam of energy 1170 MeV, data were obtained for small momentum transfers to a {pp} system with low excitation energy. A good quantitative understanding of all the measured observables is provided by the impulse approximation using known neutron-proton amplitudes. The proof of principle achieved here for the method suggests that measurements at higher energies will provide useful information in regions where the existing np database is far less reliable.

nucl-ex↗

arXiv2006

Determination of Deuteron Beam Polarizations at COSY

The vector and tensor polarizations of a deuteron beam have been measured using elastic deuteron-carbon scattering at 75.6 MeV and deuteron-proton scattering at 270 MeV. After acceleration to 1170 MeV inside the COSY ring, the polarizations of the deuterons were checked by studying a variety of nuclear reactions using a cluster target at the ANKE magnet spectrometer placed at an internal target position of the storage ring. All these measurements were consistent with the absence of depolarization during acceleration and provide a number of secondary standards that can be used in subsequent experiments at the facility.

nucl-ex↗

arXiv2006

Vector and tensor analysing powers in deuteron-proton breakup reactions at intermediate energies

Vector and tensor analysing powers of the d(pol)p->(pp)n (charge-exchange) and d(pol)p->(pn)p (non-charge-exchange) breakup reactions have been measured with the ANKE spectrometer at the COSY ring at a deuteron beam energy of 1170 MeV for small momentum transfers to the low excitation energy (pp) or (pn) systems. A quantitative understanding of the values of A_xx and A_yy for the charge-exchange reaction is provided by impulse approximation calculations. The data suggest that spin-flip isospin-flip transitions, which dominate the charge-exchange breakup of the deuteron, are also important in the non-charge-exchange reaction.

nucl-ex↗

arXiv2001

The CDF-II Online Silicon Vertex Tracker

The Online Silicon Vertex Tracker is the new CDF-II level 2 trigger processor designed to reconstruct 2-D tracks within the Silicon Vertex Detector with high speed and accuracy. By performing a precise measurement of impact parameters the SVT allows tagging online B events which typically show displaced secondary vertices. Physics simulations show that this will greatly enhance the CDF-II B-physics capability. The SVT has been fully assembled and operational since the beginning of Tevatron RunII in April 2001. In this paper we briefly review the SVT design and physics motivation and then describe its performance during the early phase (April-October 2001) of run II.

hep-ph↗