- Fall 2005: Fit dipion mass spectrum with Relativistic Breit-Wigner with Blatt-Weiskopf form factors. Both S- and P-wave decays can describe data.
- Summer 2005: Observe X(3872) → J/ψππ in challenging J/ψ →e+e- mode
- Spring 2005: Dipion mass spectrum for X(3872) → J/ψππ decay is obtained. Simple Breit-Wigner fit of X→ J/ψρ Preferred.
- Summer 2004: The Production Fractions of the X-sample
from b-hadron decays via the apparent "X-lifetime."

- Dec 4, 2003: PRL submitted with final mass measurement [PRL 93, 072001 (2004)].

- Sept 2003: CDF provided the first confirmation of Belle's discovery
of a narrow state, the X(3872), decaying into J/ψππ
at the Fermilab Quarkonium Workshop on Sept 20.

- Measurement of the Dipion Mass Spectrum
in X(3872) → J/ψ π π Decay [360 pb
^{-1}]: - The Submission to PRL [hep-ex/0512074]
- Below are the eps versions of figures and eps and tex files with tables meant for downloads, and some brief descriptions.
- A sample of 360 pb-1 is used in this analysis. The resulting J/ψππ mass
distribution is shown in:
- J/ψπ&pi Mass-- Default (before and
after cut M(ππ) > 500 MeV/c
^{2}) - J/ψπ&pi Mass-- Alternate (with
additional "inverse" cut M(ππ) < 500 MeV/c
^{2})

- J/ψπ&pi Mass-- Default (before and
after cut M(ππ) > 500 MeV/c
- The sample is divided into M(PiPi) "slices" and the J/ψππ mass distribution is fit for X(3872) signal.
- Yields are corrected for detector and selection efficiencies:
- The ψ(2S) serves as a good control sample:
- ψ(2S) Dipion mass spectrum -- Default (with only 3S1 QCD multipole Expansion fit) [PRL Version]
- ψ(2S) Dipion mass spectrum -- Alternate 1 (fit with Multipole Expansion and older model of Brown & Cahn for contrast)
- ψ(2S) Dipion mass spectrum -- Alternate 2 (fit with various models)
- Table of Fit results for ψ(2S) + tex source
- Efficiency corrected DiPion Mass Spectrum for X(3872) fit to various models:

-- QCD multipole expansion model for C-odd charmonia

-- Relativistic Briet-Wigner model of J/ψρ for C-even states (charmonia or not)- Default ππ Mass Spectrum (fit with Multipole Expansion for C-odd charmonia and J/ψρ hypotheses)
- Simplified version - (fit with Multipole Expansion only)
- Simplified version - (fit with J/ψρ only)

- Introduce effects of ρ-ω Interference into J/ψρ Fit Model:
- Blow-Up of ππ Spectrum fit by J/ψρ with ρ-ω interference (PRL Version with fit probability inset)
- Simplified version - (NO inset)
- Separate plots of L=0 and L=1 interference fits cccc
- Study the sensitivity of the L=0 fits on various model parameters:
- Study the sensitivity of the L=1 fits on various model parameters:
- Vary Interference Phase (φ) and Blatt-Weisskopf Radius of the X (R
_{X}) - Vary Interference Phase (φ) and Blatt-Weisskopf Radius of the ρ (R
_{ρ}) - Vary Blatt-Weisskopf Radii of the X (R
_{X}) and ρ (R_{ρ}) - Vary Interference Phase (φ) and ω-to-ρ branching ratio (R
_{3/2})

- Vary Interference Phase (φ) and Blatt-Weisskopf Radius of the X (R

- Study of the Production Fractions of the X(3872) [220 pb
^{-1}]: - A public write-up: CDF7159
- Below are the eps versions of figures meant for downloads.
- Figure 1 - Full J/ψππ Mass Distribution
- Figure 2:
- Top - ψ(2S) mass distribution
- Bottom - ψ(2S) lifetime distribution
- Figure 3 - ψ(2S) lifetime distribution around 2.5σ of ψ(2S)
- Figure 4 - Sideband-subtracted ψ(2S) lifetime distribution
- Figure 5:
- Top - X(3872) mass distribution
- Bottom - X(3872) lifetime distribution
- Figure 6 - X(3872) lifetime distribution around 2.5σ of X(3872)
- Figure 7 - Sideband-subtracted X(3872) lifetime distribution
- Figure 8:
- Top - ψ(2S) positive lifetime tails
- Bottom - X(3872) positive lifetime tails
- Observation and Mass Measurement of the X(3872) [220 pb
^{-1}]: - Paper Published in Phys. Rev. Lett. 93, 072001 (2004)
- Below are the eps versions of figures meant for downloads.

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