-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physics Letters B 01/2007; 648:156-163. · 3.95 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physical Review D 01/2007; 75:052003-1-052003-17. · 4.56 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physics Letters B 01/2006; 637:32-38. · 3.95 Impact Factor
-
J M Link,
P M Yager,
J C Anjos,
I Bediaga,
C Castromonte,
A A Machado,
J Magnin,
A Massafferi,
J M de Miranda,
I M Pepe, [......],
D Engh,
M Hosack,
W E Johns,
E Luiggi,
J E Moore,
M Nehring,
P D Sheldon,
E W Vaandering,
M Webster,
M Sheaff
[show abstract]
[hide abstract]
ABSTRACT: A high statistics measurement of the D(s)+ lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis of the two decay modes, D(s)+ --> phi(1020)pi+ and D(s)+ -->K*(892)0K+, used for the measurement. The measured lifetime is 507.4 +/- 5.5(stat) +/- 5.1(syst) fs using 8961 +/- 105 D(s)+ --> phi(1020)pi+ and 4680 +/- 90 D(s)+ --> K*(892)0K+ decays. This is a significant improvement over the present world average.
Physical Review Letters 08/2005; 95(5):052003. · 7.37 Impact Factor
-
FOCUS Collaboration,
J. M. Link,
P. M. Yager,
J. C. Anjos,
I. Bediaga,
C. Göbel,
A. A. Machado,
J. Magnin,
A. Massafferri,
J. M. de Miranda, [......],
D. Engh,
M. Hosack,
W. E. Johns,
E. Luiggi,
J. E. Moore,
M. Nehring,
P. D. Sheldon,
E. W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: We present a Kπ mass spectrum analysis of the four-body semileptonic
charm decay
D→Kπμν in the
range of 0.65 GeV/c<m<1.5 GeV/c.
We observe a non-resonant contribution of 5.30±0.74-0.96+0.99%
with respect to the total
D→Kπμν decay.
For the K892 resonance, we obtain a mass of
895.41±0.32-0.43+0.35 MeV/c, a width of
47.79±0.86-1.06+1.32 MeV/c, and a Blatt Weisskopf
damping factor parameter of 3.96±0.54-0.90+1.31 GeV.
We also report 90% CL upper limits of 4% and 0.64% for the branching
ratios
Γ(D→K1680μν)Γ(D→Kπμν)
and
Γ(D→K¯0∗1430μν)Γ(D→Kπμν),
respectively.
Physics Letters B 07/2005; 621:72-80. · 3.95 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physical Review Letters 01/2005; 95:5. · 7.37 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physics Letters B 01/2005; 607:233-242. · 3.95 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physics Letters B 01/2005; 607:69-56. · 3.95 Impact Factor
-
J M Link,
P M Yager,
J C Anjos,
I Bediaga,
C Gobel,
A A Machado,
J Magnin,
A Massafferri,
J M Miranda,
I M Pepe, [......],
D Engh,
M Hosack,
W E Johns,
E Luiggi,
J E Moore,
M Nehring,
P D Sheldon,
E W Vaandering,
M Webster,
M Sheaff
Physics Letters B 01/2005; 607:233-242. · 3.95 Impact Factor
-
J M LINK,
P M YAGER,
J C ANJOS,
I BEDIAGA,
C CASTROMONTE,
A A MACHADO,
J MAGNIN,
A MASSAFFERRI,
DE J M MIRANDA,
I M PEPE, [......],
D ENGH,
M HOSACK,
W E JOHNS,
E LUIGGI,
J E MOORE,
M NEHRING,
P D SHELDON,
E W VAANDERING,
M WEBSTER,
M SHEAFF
Physics Letters B 01/2005; 610:225-234. · 3.95 Impact Factor
-
J. M. Link,
P. M. Yager,
J. C. Anjos,
I. Bediaga,
C. Göbel,
J. Magnin,
A. Massafferri,
J. M. de Miranda,
I. M. Pepe,
E. Polycarpo, [......],
R. Mitchell,
D. Engh,
M. Hosack,
W. E. Johns,
M. Nehring,
P. D. Sheldon,
K. Stenson,
E. W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using a high statistics sample of photo-produced charm particles from
the FOCUS experiment at Fermilab, we report results of a search for
eight rare and Standard-Model-forbidden decays: D+,
Ds+-->h+/-μ-/+μ+
(with h=π,K). Improvement over previous results by a factor of 1.7-14
is realized. Our branching ratio upper limit
D+-->π+μ-μ+ of
8.8×10-6 at the 90% C.L. is below the current MSSM
R-parity violating constraint.
Physics Letters B 09/2003; 572:21-31. · 3.95 Impact Factor
-
Focus Collaboration,
J M Link,
P M Yager,
J C Anjos,
I Bediaga,
C Göbel,
J Magnin,
A Massafferri,
J M De Miranda,
I M Pepe, [......],
R Mitchell,
D Engh,
M Hosack,
W E Johns,
M Nehring,
P D Sheldon,
K Stenson,
E W Vaandering,
M Webster,
M Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using a high statistics sample of photo-produced charm particles from the FOCUS experiment at Fermilab, we report results of a search for eight rare and Standard-Model-forbidden decays: D + , D + s → h ± µ ∓ µ + (with h = π, K). Improvement over previous results by a factor of 1.7–14 is realized. Our branching ratio upper limit D + → π + µ − µ + of 8.8 × 10 −6 at the 90% C.L. is below the current MSSM R-parity violating constraint. 2003 Published by Elsevier B.V.
Physics Letters B. 01/2003; 572:21-31.
-
J.M. Link,
P.M. Yager,
J.C. Anjos,
I. Bediaga,
C. Göbel,
A.A. Machado,
J. Magnin,
A. Massafferri,
J.M. de Miranda,
I.M. Pepe, [......],
A.D. Bryant,
D. Engh,
M. Hosack,
W.E. Johns,
E. Luiggi,
M. Nehring,
P.D. Sheldon,
E.W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using data collected by the high energy photoproduction experiment FOCUS at Fermilab we study the doubly and singly Cabibbo suppressed decays D+ and . Our measurements of Γ(D+→K+π+π−)/Γ(D+→K−π+π+)=0.0065±0.0008±0.0004 and are based on samples of 189±24D+ and 567±31 reconstructed events, respectively. We also present Dalitz plot analyses of the two decay channels; the amplitude analysis of the mode is performed for the first time.
Physics Letters B. 601:10-19.
-
J.M. Link,
P.M. Yager,
J.C. Anjos,
I. Bediaga,
C. Castromonte,
A.A. Machado,
J. Magnin,
A. Massafferri,
J.M. de Miranda,
I.M. Pepe, [......],
D. Engh,
M. Hosack,
W.E. Johns,
E. Luiggi,
J.E. Moore,
M. Nehring,
P.D. Sheldon,
E.W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the weak decay-asymmetry parameter αΛc in decay. Comparing particle with antiparticle decays, we obtain the first measurement of the CP violation parameter . We obtain αΛc=−0.78±0.16±0.19 and A=−0.07±0.19±0.24 where errors are statistical and systematic.
Physics Letters B. 634:165-172.
-
J.M Link,
P.M Yager,
J.C Anjos,
I Bediaga,
C Göbel,
J Magnin,
A Massafferri,
J.M de Miranda,
A.A Machado,
I.M Pepe, [......],
R Mitchell,
D Engh,
M Hosack,
W.E Johns,
M Nehring,
P.D Sheldon,
K Stenson,
E.W Vaandering,
M Webster,
M Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the branching ratio for the Cabibbo-favored decay mode D0→K−K−K+π+. From a sample of 143±19 fully reconstructed D0→K−K−K+π+ events, we measure Γ(D0→K−K−K+π+)/Γ(D0→K−π−π+π+)=0.00257±0.00034(stat.)±0.00024(syst.). A coherent amplitude analysis has been performed to determine the resonant substructure of this decay mode. This analysis reveals a dominant contribution from φ and states.
Physics Letters B.
-
J.M. Link,
M. Reyes,
P.M. Yager,
J.C. Anjos,
I. Bediaga,
C. Göbel,
J. Magnin,
A. Massafferri,
J.M. de Miranda,
I.M. Pepe, [......],
R. Mitchell,
D. Engh,
M. Hosack,
W.E. Johns,
M. Nehring,
P.D. Sheldon,
K. Stenson,
E.W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement for the branching ratios of the Cabibbo-suppressed decay modes D0→π−π+ and D0→K−K+. We measured: Γ(D0→K−K+)/Γ(D0→π−π+)=2.81±0.10(stat)±0.06(syst), Γ(D0→K−K+)/Γ(D0→K−π+)=0.0993±0.0014(stat)±0.0014(syst), and Γ(D0→π−π+)/Γ(D0→K−π+)=0.0353±0.0012(stat)±0.0006(syst). These values have been combined with other experimental data to extract the ratios of isospin amplitudes and the phase shifts for the D→KK and D→ππ decay channels.
Physics Letters B.
-
J.M Link,
P.M Yager,
J.C Anjos,
I Bediaga,
C Göbel,
A.A Machado,
J Magnin,
A Massafferri,
J.M de Miranda,
I.M Pepe, [......],
R Mitchell,
D Engh,
M Hosack,
W.E Johns,
M Nehring,
P.D Sheldon,
K Stenson,
E.W Vaandering,
M Webster,
M Sheaff
[show abstract]
[hide abstract]
ABSTRACT: We report measurements of the charm–anticharm production asymmetries for Λc+, Σc++, Σc0, , , and Λc+(2625) baryons from the Fermilab photoproduction experiment FOCUS (E831). These asymmetries are integrated over the region where the spectrometer has good acceptance. In addition, we have obtained results for the photoproduction asymmetries of the Λc baryons as functions of pL, pT2, and xF. The integrated asymmetry for Λc+ production, (σΛc+−σΛc−)/(σΛc++σΛc−), is 0.111±0.018±0.012, significantly different from zero. The asymmetries of the excited states are consistent with the Λc asymmetry.
Physics Letters B.
-
J.M. Link,
P.M. Yager,
J.C. Anjos,
I. Bediaga,
C. Castromonte,
C. Göbel,
A.A. Machado,
J. Magnin,
A. Massafferri,
J.M. de Miranda, [......],
D. Engh,
M. Hosack,
W.E. Johns,
E. Luiggi,
J.E. Moore,
M. Nehring,
P.D. Sheldon,
E.W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: We review genetic programming principles, their application to FOCUS data samples, and use the method to study the doubly Cabibbo suppressed decay D+→K+π+π- relative to its Cabibbo favored counterpart, D+→K-π+π+. We find that this technique is able to improve upon more traditional analysis methods. To our knowledge, this is the first application of the genetic programming technique to High Energy Physics data.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
-
J.M Link,
P.M Yager,
J.C Anjos,
I Bediaga,
C Göbel,
A.A Machado,
J Magnin,
A Massafferri,
J.M de Miranda,
I.M Pepe, [......],
A.D Bryant,
D Engh,
M Hosack,
W.E Johns,
M Nehring,
P.D Sheldon,
K Stenson,
E.W Vaandering,
M Webster,
M Sheaff
[show abstract]
[hide abstract]
ABSTRACT: Using data collected by the FOCUS experiment at Fermilab, we report the discovery of the decay modes D0→K−π+π+π+π−π− and D0→π+π+π+π−π−π−. With a sample of 48±10 reconstructed D0→K−π+π+π+π−π− decays and 149±17 reconstructed D0→π+π+π+π−π−π− decays, we measure the following relative branching ratios: Γ(D0→K−π+π+π+π−π−)/Γ(D0→K−π+π+π−)=(2.70±0.58±0.38)×10−3,Γ(D0→π+π+π+π−π−π−)/Γ(D0→K−π+π+π−)=(5.23±0.59±1.35)×10−3,Γ(D0→π+π+π+π−π−π−)/Γ(D0→K−π+π+π+π−π−)=1.93±0.47±0.48. The first errors are statistical and the second are systematic. The branching fraction of the Cabibbo suppressed six-body decay mode is measured to be a factor of two higher than the branching fraction of the Cabibbo favored six-body decay mode.
Physics Letters B.
-
J.M. Link,
M. Reyes,
P.M. Yager,
J.C. Anjos,
I. Bediaga,
C. Göbel,
J. Magnin,
A. Massafferri,
J.M. de Miranda,
I.M. Pepe, [......],
R. Mitchell,
D. Engh,
M. Hosack,
W.E. Johns,
M. Nehring,
P.D. Sheldon,
K. Stenson,
E.W. Vaandering,
M. Webster,
M. Sheaff
[show abstract]
[hide abstract]
ABSTRACT: We have performed a search for CPT violation in neutral charm meson oscillations. While flavor mixing in the charm sector is predicted to be small by the Standard Model, it is still possible to investigate CPT violation through a study of the proper time dependence of a CPT asymmetry in right-sign decay rates for D0→K−π+ and . This asymmetry is related to the CPT violating complex parameter ξ and the mixing parameters x and y: ACPT∝(Reξ)y−(Imξ)x. Our 95% confidence level limit is −0.0068<(Reξ)y−(Imξ)x<0.0234. Within the framework of the Standard Model Extension incorporating general CPT violation, we also find 95% confidence level limits for the expressions involving coefficients of Lorentz violation of (−2.8<N(x,y,δ)(Δa0+0.6ΔaZ)<4.8)×10−16 GeV, (−7.0<N(x,y,δ)ΔaX<3.8)×10−16 GeV, and (−7.0<N(x,y,δ)ΔaY<3.8)×10−16 GeV, where N(x,y,δ) is the factor which incorporates mixing parameters x, y and the doubly Cabibbo-suppressed to Cabibbo-favored relative strong phase δ.
Physics Letters B.