Stephen L. Olsen's BES Analysis Home Page

Observation of a narrow p-pbar state with mass near 2m_p in radiative J/psi decays

Observation of a near-threshold enhancement in the p-pbar mass spectrum from radiative J/psi --> gamma p pbar decays
Final version of the paper that was submitted to Phys. Rev. Letters.
(5 pages in postscript format 7/2/03)

Slides for my DPF2003 talk: Observation of a narrow ppbar enhanceme,nt near Mppbar in J/psi --> gamma ppbar

in pdf format (revised version posted 4/03/03)
same file in .ppt format

Observation of a near-threshold enhancement in the p-pbar mass spectrum from radiative J/psi --> gamma p pbar decays
Proposed revised version of the paper submitted for publication to Phys. Rev. Letters.
(5 pages in postscript format 3/31/03)

Observation of a near-threshold enhancement in the p-pbar mass spectrum from radiative J/psi --> gamma p pbar decays
The original paper submitted for publication to Phys. Rev. Letters.
(5 pages in postscript format 3/07/03)
Same paper in .pdf format.

A narrow p pbar enhancement near Mpp=2mp in J/psi-->gamma ppbar
Slides for my talk at the Feb 24, 2003 Nihon Dai Symposium on Hadron Spectroscopy, etc
(38 pages in pdf format 3/03/03)

Observation of a near-threshold enhancement in the proton-antiproton mass spectrum from radiative J/psi-->gamma p pbar decays
Article for the proceedings of the Feb 24, 2003 Nihon Dai Symposium on Hadron Spectroscopy, etc
(6 pages in postscript format posted 3/27/03)
The same paper in .pdf format.

Update on J/psi --> gamma p pbar
Slides presented at the Jan 9, 2003 UH-BES meeting
(8 pages in pdf format 1/10/03)

An updated analysis memo on the observation of a near-threshold enhancement in the p-pbar mass spectrum from radiative J/psi --> gamma p pbar decays. This version includes the possibilie mass and width biasses seen by Xiaobin
Jan 28, 2003
(14 pages in postscript format 1/28/03)

Observation of a low mass enhancement in radiative J/psi--> gamma ppbar decays
Prepared for the proceedings of BES2002, Chengdu.
(7 pages in postscript format 8/19/02)

Comment on the suggestion that the low mass ppbar peak we see in J/psi--> gamma ppbar has anything to do with the eta(1760)
Materials prepared for a BES conference call July 8 2002.
(8 pages in pdf format 7/8/02)

Fifth version of an analysis memo on the observation of a low mass p pbar state
This supersedes the analysis memos of March 8, 2001, September 12, 2001, October 5 2001, December 20, 2001 and January 11, 2002.
(15 pages in postscript format 1/15/02)

Seventh draft of a paper on the observation of a low mass p pbar state
(two-column postscript format, posted 1/15/02)

pipi masses recoiling from a phi in J/psi->K+K-pi+pi-
(postscript posted 5/21/02)
K+K- masses recoiling from a phi in J/psi->K+K-K+K-
(postscript posted 5/21/02)
Update on J/psi-->gamma p pbar.
Slides for the Jan 11 2002 US-BES group video meeting
(PDF format, posted 1/11/02)
Update on J/psi-->gamma p pbar.
Slides for the Dec 7 2001 US-BES group video meeting
(PDF format, posted 12/7/01)
slides on the observation of a low mass p pbar state.
Prepared for the Nov 29 US-China BES group video meeting
(PDF format, posted 11/28/01)
ppbar mass from B to ppbar K decays.
From the Belle experiment (reported at the KEK Topical Conf Nov 22, 2001)
(PDF format, posted 12/27/01)

Proposal for data taking between 2 and 3 GeV

Proposal for running BEPC between 2 and 3 GeV (posted 7/5/01)

Preliminary results of a study of J/psi-> gamma p pbar in the 1999-2000 BES II data

A study of J/psi to gamma p pbar with the 1999-2000 BES II data (posted 6/29/01)

Preliminary results from a search for J/psi-> gamma xi(2230) in the 2000 BES II data

Search for J/psi to gamma xi(2230) with BES II data (posted 3/8/01)

Plot of 3 pi mass spectrum from J/psi-> 3pi gamma

M(pi+pi-pi0) from J/psi -> 3pi gamma (posted 6/2/01)

A description of my analysis of psi' and e+e- ->omega pi0 and K*K decays:

• Isospin violations in psi(2S)--> vector plus pseudoscalar decays (revised version posted 9/3/98)

Phys Rev D brief report:

• Psi(2S)-->Gamma Eta' and Gamma eta (revised version posted 1/27/98)

Photos of the Bear Machinery Shop, Kaneohe Hawaii:

• Large bending machine
• Work bench area
• Assembly area
• Machine area
• Welding table (surface is true to 50 microns)
• Welding table plus crane
• Coffee break
• Turret lathe
• Comparing pot-bellies 1
• Comparing pot-bellies 2
• It's a draw!

Photos of some of the work done by Bear Machinery, Kaneohe Hawaii:

• jaw for a remote manipulator
• Storage canisters
• Part of a large steel hopper
• Completed hopper

"Live" BES Analysis Memos

• Psi(2S) --> VP; The other modes. (preliminary version posted on 9/18/97)
• Psi(2S) --> Gamma eta' and Gamma eta (revised version posted on 8/1/97)
• Psi(2S) --> Gamma eta'; eta'-->gamma rho mode. Plots of m(pi+pi-) vs/and m(pi+pi- gamma) (posted on 8/5/97)
• Psi(2S) --> Gamma eta'; eta'-->pi+pi- eta mode. Plots of m(gamma gamma) vs/and m(pi+pi- gamma gamma) (posted on 8/5/97)

"Stale" BES Analysis Memos

• Study of Psi(2S) --> Gamma + 4 charged tracks (Updated version posted on 4/4/97)
• Observation of Psi(2S)-->Gamma Eta' (revised 11/26/96)
• Study of chi_c-->K+K-K+K-' (11/20/96)
• Do the BES results preclude the vector glueball explanation for the rho-pi/K*K puzzle? (9/3/96)

1996 Summer Conference Papers

• Puzzles in hadronic charmonium decays (9/18/96) This is a writeup of my talk at the Quarkonium 1996 meeting at the University of Illinois at Chicago on June 15, 1996.
• Charmonium decays to axialvextor plus pseudoscalar mesons submitted to the International Meeting on High Energy Physics, Warsaw July, 1996.
• Charmonium decays to baryon-antibaryon pairs Ling Jun Pan's contributed paper to the meeting of the Division of Particles and Fields of the American Physical Society, Minneapolis August, 1996
• Charmonium decays to strange axialvector-pseudoscalar mesons Daniela Paluseli's contributed paper to the meeting of the Division of Particles and Fields of the American Physical Society, Minneapolis August, 1996

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Old BES Analysis Memos

• Comparison of psi' --> b_1 pi and J/psi --> b_1 pi (5/21/96)
• Search for psi'--> Omega- Omega-bar (5/15/96)
• Search for psi'--> Xi(1530) Xi-bar(1530) (5/15/96)
• Analysis of J/psi and psi'--> Axialvector plus Psuedoscalar Mesons (4/23/96)

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Plots for CUSeeMe/PICTEL Discussions

PICTEL talk at SLAC BES group meeting May 10, 1996

• Title: Study of psi' and J/psi --> omega pi+pi-; omega f_2; gamma f_2
• Motivation and discussion of technique (5/10/96)
• omega pi+pi- and omega f_2: list of selection cuts (5/10/96)
• Fig 1a-d: J/psi--> pi+pi-pi+pi-pi0, various mass distributions (5/10/96)
• Fig 2a-d: psi'--> pi+pi-pi+pi-pi0, various mass distributions (5/10/96)
• omega pi+pi- and omega f_2 branching fraction calculations (5/10/96)
• Fig 3: Fit to J/psi->omega pi+pi- (5/10/96)
• Fig 4: Fit to psi'->omega pi+pi- (5/10/96)
• Fig 5: fit to J/psi -> omega f_2 with "underestimated" background (5/10/96)
• Fig 6: fit to J/psi -> omega f_2 with "overestimated" background (5/10/96)
• Fig 7: fit to psi' -> omega f_2 with "underestimated" background (5/10/96)
• gamma f_2 selection cuts and branching fraction calculations (5/10/96)
• Fig 8: Fit to J/psi-> gamma f_2 (bkgrnd 1) (5/10/96)
• Fig 9: Fit to J/psi->gamma f_2 (bkgrnd 2) (5/10/96)
• Fig 10: Fit to psi'-->gamma f_2 mass and width of f2 fixed at PDG values (4/30/96)
• Is the f_2 at the right mass? (5/10/96)
• Fig 11: Fit to psi'-->gamma f_2 mass and width of f2 allowed to float (4/30/96)
• Fig 12: Fit to psi'-->gamma f_2 mass and width of f2 fixed at PDG values. 94 data only(5/5/96)
• Fig 13: Fit to psi'-->gamma f_2 with mass of f2 allowed to float 94 data only(5/5/96)

CUSeeMe talk at SLAC BES group meeting April 12, 1996

• Title: Study of exclusive psi' --> Axialvector Psuedoscalar decays
• Motivation and discussion of psi'--> b1 pi selection and Br calculation (4/12/96)
• Fig 1a-f: b1(1235) --> omega(780) pi, various mass distributions (4/12/96)
• Fig 2: Fit to b1 -> omega pi with "overestimated" background (4/12/96)
• Fig 3: fit to b1 -> omega pi with "underestimated" background (4/12/96)
• psi'-> k1(1270) k event selection and Br calculation (4/12/96)
• Fig 4: various k+ k- pi+ pi- mass distributions (4/12/96)
• Fig 5: Fit to k+rho (+cc) mass distribution with "overestimated" bkgd (4/12/96)
• Fig 6: Fit to k+rho (+cc) mass distribution with "underestimated" bkgd (4/12/96)
• psi'--> k1(1400) k Br calculation (4/12/96)
• Fig 7: Fit to k* pi mass spectrum (4/12/96)
• Discussion of a study of J/psi decays using psi'-->pi+pi-J/psi; J/psi-->k+k-pi+pi-(4/12/96)
• Fig 8a-f: J/psi-k+k-pi+pi- mass distributions (4/12/96)
• Fig 9: fit to k rho from J/psi decays --looking for Jpsi->k1(1270)k (4/12/96)
• Fig 10: fit to k* pi from J/psi decays --looking for J/psi->k1(1400) k (4/12/96)

Various Plots: April 9-10, 1996

• fit to the k1->k+rho signal using Bill Dunwoodie's concocted line shape (4/10/96)
• k+k- masses for k rho masses above 2400 in psi'->k+k-pi+pi- decays (4/9/96)
• k+k- masses recoiling against pi+pi- in 1270 region in psi'->k+k-pi+pi- decays (4/9/96)

PICTEL meeting with CSU: April 4, 1996

• Title: Search for k1(1270) in psi'-->k0k+pi-pi0 +cc decays
• Introduction and selection cuts (4/4/96)
• Fig 1: 95 data: precut distributions (4/4/96)
• Description of invariant mass distributions and fits(4/4/96)
• Fig 2: k0 pi+ pi0 (+cc) mass distribution (4/4/96)
• Fig 3: Fit to k0 pi+ pi0 (+cc) mass distribution (4/4/96)
• Fig 4: k+ pi- pi0 (+cc) mass distribution (4/4/96)
• Fig 5: Fit to k+ pi- pi0 (+cc) mass distribution (4/4/96)
• Fig 6: pi+ pi0 (+cc) mass distribution (4/4/96)
• Fig 7: k pi (+cc) mass distribution (4/4/96)
• Branching fraction calculations(4/4/96)
• A comparison with J/psi decays using psi'-->pi+pi-J/psi; J/psi-->k+k-pi+pi-(4/4/96)
• Fig 8a-f: J/psi-k+k-pi+pi- mass distributions (4/4/96)
• Fig 9: fit to k1(1400) from J/psi decays (4/4/96)

CUSeeMe meeting with UTD and CSU: March 28, 1996

• Title: Br's for psi'-->k1(1270)^+k^- and k1(1400)^+k^- on 3/28/96
• Introduction (3/28/96)
• K1(1270) selection/Br calculation (3/28/96)
• Fig. 1: k+k-pi+pi- event selection figures (3/28/96)
• Fig. 2: K1(1270) mass plots (3/28/96)
• Fig. 3: K1(1270) fit results (3/28/96)
• K1(1400) selection/Br calculation (3/28/96)
• Fig. 4: K1(1400) event selection figures (3/28/96)
• Fig. 5: K1(1400) fit results (3/28/96)

CUSeeMe meeting with UTD and CSU: March 15, 1996

• Title: psi'-->k*k* and k*k2*
• OHP #1 introduction (3/15/96)
• OHP #2 event selection (3/15/96)
• OHP #3 Figs 1a - 1f (3/15/96)
• OHP #4 Figs 2a and b (3/15/96)
• OHP #5 Fig 3 (3/15/96)
• OHP #6 Acceptance and preliminary results (3/15/96)

CUSeeMe talk at SLAC BES meeting December 15, 1995

• Title: psi'--> pi+pi-k+k- decays: (psi' -> k*k*, k*k_2*, k1(1270)k)
• pi pi k k discussion
• Fig 1: k*k* and k*k_2* selection
• Fig 2: k*k* and k*k_2* fit results
• Fig 3: k-rho selection
• Fig 4: k-rho fit results
• Fig 5: k* pi fit results
• Fig 6: Q0 selection results
• Fig 7: Q0 fit results

CUSeeMe talk at the October 6, 1995 BES Meeting

• Title: pi+pi-pi+pi-pi0 events; overview:
• pi+pi-pi+pi-pi0 overview discussion
• Fig 1: pi+pi-pi+pi-p0 overview plots
• pi+pi-pi+pi-pi0 events with one rho:
• rho pi discussion
• Fig 2: rho pi results
• Fig 3: fit to the omicron?
• pi+pi-pi+pi-pi0 events with two rhos:
• rho a2 discussion
• Fig 4: 1994 data rho a2 results
• Fig 5: 1995 data rho a2 results
• Fig 6: fit to the a2
• pi+pi-pi+pi-pi0 events with an omega:
• omega pi pi discussion
• omega pi pi results
• Fig 7: omega fit results
• Fig 8: f2(1270) fit results
• Fig 9: b1(1235) results
• Fig 10: b1(1235) fit results

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"Ancient" BES analysis memos

• Number of psi's and: fig 1; fig 2; fig 3; fig 4; and fig 5.
• Br psi' --> p pbar and figures.
• Br psi' --> Lambda Lambdabar and figures.
• Br psi' --> Sigma0 Sigma0bar and figures.
• Br psi' --> Xi- Xi-bar and figures.

Other Pages

• Steve Olsen's public home page
• Steve Olsen's Sunday Morning
• BES
• BELLE
• UH Elementary Particle Physics

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Last modified: March 9, 1995
Stephen L. Olsen / solsen@uhhepj.phys.hawaii.edu