3,298,083 research outputs found
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
Extracting Boer-Mulders functions from p+D Drell-Yan processes
No full textWe extract the Boer- Mulders functions of valence and sea quarks in the proton from unpolarized p + D Drell- Yan data measured by the FNAL E866 Collaboration. Using these Boer- Mulders functions, we calculate the cos2 phi asymmetries in unpolarized pp Drell- Yan processes, both for the FNAL E866/ NuSea and the BNL Relativistic Heavy Ion Collider experiments. We also estimate the cos2 phi asymmetries in the unpolarized p (P) over bar Drell- Yan processes at GSI.Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)37ARTICLE5null7
Measurements of the decays B-0 -> (D)over-bar(0) p(p)over-bar, B0 -> (D)over-bar*(0) p(p)over-bar, B-0 -> D- p(p)over-bar pi(+), and B-0 -> D*(-) p(p)over-bar pi(+)
No full textWe present measurements of branching fractions of B-0 decays to multibody final states containing protons, based on 232x10(6) Upsilon(4S)-> B (B) over bar decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. We measure the branching fractions B(B-0 ->(D) over bar (0)p (p) over bar)=(1.13 +/- 0.06 +/- 0.08)x10(-4), B(B-0 ->(D) over bar (*0)p (p) over bar)=(1.01 +/- 0.10 +/- 0.09)x10(-4), B(B-0 -> D(-)p (p) over bar pi(+))=(3.38 +/- 0.14 +/- 0.29)x10(-4), and B(B-0 -> D(*-)p (p) over bar pi(+))=(4.81 +/- 0.22 +/- 0.44)x10(-4) where the first error is statistical and the second systematic. We present a search for the charmed pentaquark state, Theta(c)(3100) observed by H1 and put limits on the branching fraction B(B-0 ->Theta(c)(p) over bar pi(+))xB(Theta(c)-> D(*-)p)Theta(c)(p) over bar pi(+))xB(Theta(c)-> D(-)p)< 9x10(-6). Upon investigation of the decay structure of the above four B-0 decay modes, we see an enhancement at low p (p) over bar mass and deviations from phase-space in the (D) over bar(p) over bar and (D) over bar invariant mass spectra
P. D. Grogan and H. J. Hindle
No full text"SX16247 Pte. P. D. Grogan
SX15874 Pte. H. J. Hindle
10/48 Bn. A.I.F. 1943 -1943"SX16247 Private P. D. Grogan.
SX15874 Private H. J. Hindle.
10/48 Battalion, Australian Imperial Forces 1942 - 1943
Enhanced electron screening in d(d,p)t for deuterated Ta*
No full textThe recent observation of a large electron screening
effect in the d(d, p)t reaction using a deuterated Ta target has been
confirmed using somewhat different experimental approaches: for the electron screening potential energy. The high
value arises from the environment of the deuterons in the Ta
matrix, but a quantitative explanation is missing
Measurement of the anti-p d annihilation at rest
No full textThe measurement of different reactions of ~d annihilation at rest in a gaseous target has
been performed using the OBELIX spectrometer at LEAR (CERN). A strong deviation
from the OZI-rule prediction was found from the measurement of the ratio R = ~b~r/to~r in
two regions of proton momenta, P 400 MeV/c: R(&~r-/toTr-) =
(133 + 26)× 10 -3 and (113 + 30)× 10 -3, respectively. These values are about 30 times
greater than the theoretical prediction. For the first time the excitation of the A-resonance
was observed among the final-state products of ~d annihilation. The existence of a broad
enhancement in the 4~r invariant mass at m = 1480 MeV, seen in previous experiments, was
confirmed. A = 100 MeV downward shift of the bump position, when the proton momentum
increased up to P > 400 MeV/c, was also observed, while the positions of to, p and
f2(1270) did not change with the proton momentum. The following branching ratios were
measured: BR(~d ~ 7r-~bp) = (6.62 + 0.49) × 10 -4, for P < 200 MeV/c; BR(pd --* zr-~bp)
= (0.95 + 0.22) × 10 -4, for P > 400 MeV/c; BR(~d ~ r-top) = (49.7 + 8.9) x 10 -4, for P
400 MeV/c; BR(~d --+
2~--zr+p) = (150 + 6) × 10 -4, for P < 200 MeV/c; BR(~d --* 2~--zr+p) = (16.6 + 0.9) ×
10 -4, for P > 400 MeV/c; BR(~d --* 37r-2~r+p) = (326 + 12) × 10 -4, for P < 200 MeV/c;
BR(~d --+ 37r-2~-+p) --- (44 _ 7) × 10 -4, for P > 400 MeV/c; BR(~d ---, AK+~ "-) = (0.96 +
0.19) × 10 -4, for P > 400 MeV/c; BR(pd ~ AK+~--~ "°) ---- (3.5 + 0.8) × 10 -4, for P > 400
MeV/c; BR(~p ~ 2~r-27r +) = (540 + 20) X 10-4; BR(~p --* 3~-3~ "+) = (251 + 21) x 10 -4
Gauged N=3, D=4 supergravity: A new web of marginally connected vacua
No full textWe analyze the vacuum structure of N=3,D=4 supergravity coupled to 9 vector multiplets with gauge group SO(3)×SU(3). Aside from the central N=3 AdS4 vacuum at the origin, on which the supermultiplet structure reproduces the massless sector of M-theory compactified on N0,1,0, we find a rich structure of AdS4 vacua preserving N=0,1,2,3 supersymmetry. These new vacua are arranged in a manifold spanned by scalar fields corresponding to exactly marginal deformations of the dual CFT. This manifold has the form T3/K, where K is a discrete subgroup of the gauge group: N=3,2 and 1 vacua correspond, respectively, to a point, a line and a surface in the three-dimensional vacuum manifold. We study RG flows from the central N=3 vacuum and elaborate on the possible higher dimensional origin of the new vacua. For the reader's convenience we also provide a review of the embedding tensor formulation of D=4, N=3 gauged supergravities. In particular we provide formulas involving the fermion shift tensors and mass matrices in N=3 theories, which can be applied to a generic gauging
Measurement of the B-d(0)-(B)over-bar(d)(0) flavor oscillation frequency and study of same side flavor tagging of B mesons in p(p)over-bar collisions
No full textB-d(0)-(B) over bar(d)(0) oscillations are observed in ''self-tagged'' samples of partially reconstructed B mesons decaying into a lepton and a charmed meson collected in p (p) over bar collisions at root s = 1.8 TeV. A flavor tagging technique is employed which relies upon the correlation between the flavor of B mesons and the charge of a nearby particle. We measure the flavor oscillation frequency to be Delta m(d) = 0.471 (+0.078)(-0.068) +/- 0.034 ps(-1). The tagging method is also demonstrated in exclusive samples of B-u(+) --> J/psi K+ and B-d(0)-->J/psi K-*0(892), where similar flavor-charge correlations are observed. The tagging characteristics of the various samples are compared with each other, and with Monte Carlo simulations. [S0556-2821(99)05901-9]
Enhanced electron screening in d(d, p)t for deuterated Ta
No full textThe recent observation of a large electron screening effect in the d(d, p)t reaction using a deuterated Ta target has been confirmed using somewhat different experimental approaches: U-e = 309 +/- 12 eV for the electron screening potential energy. The high U, value arises from the environment of the deuterons in the Ta matrix, but a quantitative explanation is missing
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