| |
Records |
Links  |
|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
|
| |
Title |
Search for the decay modes D-0 -> e(+) e(-), D-0 -> mu(+) mu(-), and D-0 -> e(+/-) μ-/+ |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
| |
Volume |
86 |
Issue |
3 |
Pages |
032001 - 10pp |
|
| |
Keywords |
|
|
| |
Abstract |
We present searches for the rare decay modes D-0 -> e(+) e(-), D-0 -> mu(+) mu(-), and D-0 -> e(+/-) mu(-/+) in continuum e(+) e(-) -> c (c) over bar events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 fb(-1). These decays are highly Glashow-Iliopoulos-Maiani suppressed but may be enhanced in several extensions of the standard model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D-0 -> mu(+) mu(-) channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: B(D-0 -> e(+) e(-)) < 1.7 x 10(-7), B(D-0 -> mu(+) mu(-)) within [0.6,8.1] x 10(-7), and B(D-0 -> e(+/-) mu(-/+)) < 3.3 x 10(-7). |
|
| |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, LAPP, CNRS IN2P3, F-74941 Annecy Le Vieux, France |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1550-7998 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000306993800002 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1120 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
BABAR Collaboration (Lees, J.P. et al); Bernabeu, J.; Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
|
| |
Title |
Observation of Time-Reversal Violation in the B-0 Meson System |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
|
| |
Volume |
109 |
Issue |
21 |
Pages |
211801 - 8pp |
|
| |
Keywords |
|
|
| |
Abstract |
Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B-0 or (B) over bar (0)), and J/psi K-L(0) or c (c) over barK(S)(0) final states (referred to as B+ or B-), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, (B) over bar (0) -> B- and B- -> (B) over bar (0), as a function of the time difference between the two B decays. Using 468 X 10(6) B (B) over bar pairs produced in Y(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding Delta S-T(+) = -137 +/- 0.14(stat) +/- 0.06(syst) and Delta S-T(-) = 1.17 +/- 0.18(stat) +/- 0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation. |
|
| |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, LAPP, F-74941 Annecy Le Vieux, France |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0031-9007 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000311283800001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1220 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
|
| |
Title |
Search for a low-mass scalar Higgs boson decaying to a tau pair in single-photon decays of Y(1S) |
Type |
Journal Article |
| |
Year |
2013 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
| |
Volume |
88 |
Issue |
7 |
Pages |
071102 - 8pp |
|
| |
Keywords |
|
|
| |
Abstract |
We search for a low-mass scalar CP-odd Higgs boson, A(0), produced in the radiative decay of the upsilon resonance and decaying into a tau(+)tau(-) pair: Y(1S) -> gamma A(0). The production of Y(1S) mesons is tagged by Y(2S) -> pi(+)pi(-) Y(1S) transitions, using a sample of (98.3 +/- 0.9) x 10(6) Y(2S) mesons collected by the BABAR detector. We find no evidence for a Higgs boson in the mass range 3: 5 <= m(A)0 <= 9: 2 GeV, and combine these results with our previous search for the tau decays of the light Higgs in radiative Y(3S) decays, setting limits on the coupling of A(0) to the b (b) over bar quarks in the range 0.09-1.9. Our measurements improve the constraints on the parameters of the next-to-minimal-supersymmetric Standard Model and similar theories with low-mass scalar degrees of freedom. |
|
| |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1550-7998 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000326039300001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1632 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
DEPFET collaboration (Alonso, O. et al); Boronat, M.; Esperante-Pereira, D.; Fuster, J.; Garcia, I.G.; Lacasta, C.; Oyanguren, A.; Ruiz, P.; Timon, G.; Vos, M. |
|
| |
Title |
DEPFET Active Pixel Detectors for a Future Linear e(+)e(-) Collider |
Type |
Journal Article |
| |
Year |
2013 |
Publication |
IEEE Transactions on Nuclear Science |
Abbreviated Journal |
IEEE Trans. Nucl. Sci. |
|
| |
Volume |
60 |
Issue |
2 |
Pages |
1457-1465 |
|
| |
Keywords |
Active pixel sensor; DEPFET; linear collider; vertex detector |
|
| |
Abstract |
The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 μm. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling, and services. In this paper, the status of the DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear e(+)e(-) collider. |
|
| |
Address |
[Alonso, O.; Casanova, R.; Dieguez, A.] Univ Barcelona, E-08028 Barcelona, Spain, Email: marcel.vos@ific.uv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0018-9499 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000320856800029 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1489 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
|
| |
Title |
Time-integrated luminosity recorded by the BABAR detector at the PEP-II e(+)e(-) collider |
Type |
Journal Article |
| |
Year |
2013 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
|
| |
Volume |
726 |
Issue |
|
Pages |
203-213 |
|
| |
Keywords |
BABAR; Integrated luminosity; Electron-positron collider; PEP-II |
|
| |
Abstract |
We describe a measurement of the time-integrated luminosity of the data collected by the BABAR experiment at the PEP-II asymmetric-energy e(+)e(-) collider at the Upsilon(4S), Upsilon(3S), and Upsilon(2S) resonances and in a continuum region below each resonance. We measure the time-integrated luminosity by counting e(+)e(-)-> e(+)e(-) and (for the Upsilon(4S) only) e(+)e(-)->mu(+)mu(-) candidate events, allowing additional photons in the final state. We use data-corrected simulation to determine the cross-sections and reconstruction efficiencies for these processes, as well as the major backgrounds. Due to the large cross-sections of e(+)e(-)-> e(+)e(-) and e(+)e(-)->mu(+)mu(-), the statistical uncertainties of the measurement are substantially smaller than the systematic uncertainties. The dominant systematic uncertainties are due to observed differences between data and simulation, as well as uncertainties on the cross-sections. For data collected on the Upsilon(3S) and Upsilon(2S) resonances, an additional uncertainty arises due to Upsilon -> e(+)e(-)X background. For data collected off the Upsilon resonances, we estimate an additional uncertainty due to time dependent efficiency variations, which can affect the short off-resonance runs. The relative uncertainties on the luminosities of the on-resonance (off-resonance) samples are 0.43% (0.43%) for the Upsilon(4S), 0.58% (0.72%) for the Upsilon(3S), and 0.68% (0.88%) for the Upsilon(2S). |
|
| |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.; Bettoni, D.; Bozzi, C.; Piemontese, L.; Santoro, V.; Passaggio, S.; Robutti, E.; Neri, N.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Perez, A.; Walsh, J.; Anulli, E.; Ferrarotto, F.; Gioi, L. Li; Mazzoni, M. A.; Piredda, G.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 A Le Vieux, France, Email: abi@slac.stanford.edu |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000323557200028 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1561 |
|
| Permanent link to this record |
