Steve Maxfield
920 GeV protons on 27.6 GeV electrons or positrons →318 GeV centre of mass H1 (was) in the HERA ep ring at DESY
Data taking ended in July 2007… HERA-I HERA-II e-e- ~20 pb -1 ~290 pb -1 e+e+ ~100 pb -1 ~270 pb -1 ~1 fb -1 collected by H1+ZEUS Finale: Low Energy Run GeV to measure F L structure function. Finale: Low Energy Run GeV to measure F L structure function. Meanwhile…
H1 Liverpool has grown! John Dainton Erwin Gabathuler Tim Greenshaw Max Klein Thomas Kluge Paul Laycock Steve Maxfield Andy Mehta Girish Patel AJ Rahmat
…and H1 remains Active: Huge amount of data still to be analysed. Program to produce combined H1+ZEUS results underway Huge amount of data still to be analysed. Program to produce combined H1+ZEUS results underway
H1 Publications in 2007: Three- and Four-jet Production at Low x at HERA Measurement of Isolated Photon Production in Deep-Inelastic Scattering at HERA Measurement of Deeply Virtual Compton Scattering and its t-dependence at HERA Dijet Cross Sections and Parton Densities in Diffractive DIS at HERA Measurement of Inclusive Jet Production in Deep-Inelastic Scattering at High Q 2 and Determination of the Strong Coupling Charged Particle Production in High Q 2 Deep-Inelastic Scattering at HERA Search for Baryonic Resonances Decaying to Xi pi in Deep-Inelastic Scattering at HERA Tests of QCD Factorisation in the Diffractive Production of Dijets in Deep-Inelastic Scattering and Photoproduction at HERA Search for Lepton Flavour Violation in ep collisions at HERA A few recent and/or ongoing analyses…
Cross section at Low Q 2 and x (Preliminary) Reduced Cross section at Low Q 2 Uses normal and shifted vertex data Uses events with ISR. Mom conservation and careful track validation with the BST. Will be Final results for Q 2 <~1GeV 2 more to come for higher Q 2 Precursor to F L measurement at low Q 2 Other measurements underway: σ at high Q 2, y 920 GeV beam → F L high Q 2 ‘Bulk’ 2000 data: highest precision F 2 data in range Q 2 12 – 100 GeV 2 NC high Q 2 : dσ/dQ 2 :all HERA data (I+II) Pol n asymmetry: 0304e + / 0405e - xF 3 : 0304e + / 0405e - Analysis of 460 / 575 GeV data started (Preliminary) Reduced Cross section at Low Q 2 Uses normal and shifted vertex data Uses events with ISR. Mom conservation and careful track validation with the BST. Will be Final results for Q 2 <~1GeV 2 more to come for higher Q 2 Precursor to F L measurement at low Q 2 Other measurements underway: σ at high Q 2, y 920 GeV beam → F L high Q 2 ‘Bulk’ 2000 data: highest precision F 2 data in range Q 2 12 – 100 GeV 2 NC high Q 2 : dσ/dQ 2 :all HERA data (I+II) Pol n asymmetry: 0304e + / 0405e - xF 3 : 0304e + / 0405e - Analysis of 460 / 575 GeV data started Results out next year
S determination from Inclusive jets in DIS Use ratio of incl. jet to NC cross sections →reduced systematic, pdf errors Dominating theory error still scale uncertainty ( can reduce at expense of increased stat errors by limiting Q 2 range. ‘Best’ result: Dominating theory error still scale uncertainty ( can reduce at expense of increased stat errors by limiting Q 2 range. ‘Best’ result:
Charm and Beauty Measurements – an ongoing analysis Now: Combining info from track and secondary vertex significances using Neural Net S 1, S 2, S 3, N TRACK, P T TRACK1, P T TRACK2, P T Jet, SV Sig., SV Mult. Very good b/c discrimination S 1, S 2, S 3, N TRACK, P T TRACK1, P T TRACK2, P T Jet, SV Sig., SV Mult. Very good b/c discrimination Results with full 06/07 data out next year Prelim result in 2007
FTD Major Improvements in track reconstruction FTD segment linking cuts tuned. Use beam line constraint for 1-module tracks. Pick up more clusters in the Kalman filter step. Outlier rejection implemented in Kalman filter track fit. Primary vertex fit cuts tuned. 70% more vertex-fitted tracks! Major Improvements in track reconstruction FTD segment linking cuts tuned. Use beam line constraint for 1-module tracks. Pick up more clusters in the Kalman filter step. Outlier rejection implemented in Kalman filter track fit. Primary vertex fit cuts tuned. 70% more vertex-fitted tracks! “use FTD tracks in the HFS” FTD finally ‘comes of age’: So where is it now?
Is that Irony or Ironmongery?
HERA=H1+ZEUS Combine H1 and ZEUS analyses 2 x statistics ~1fb -1 Improved systematics Make combined fits best possible precision for seminal HERA results Combine H1 and ZEUS analyses 2 x statistics ~1fb -1 Improved systematics Make combined fits best possible precision for seminal HERA results
e.g. S from inclusive jets in DIS N ext p
NC e + p NB still only HERA I!
Multi-lepton final states…
Conclusions H1 data taking has finished but the exploitation phase is in full swing and the highest precision results are still to come. H1+ZEUS → HERA results beginning to appear. Effort will still be needed – this is good physics cheap at the price. May not be the end of ep collider physics… For now…we note that: H1 data taking has finished but the exploitation phase is in full swing and the highest precision results are still to come. H1+ZEUS → HERA results beginning to appear. Effort will still be needed – this is good physics cheap at the price. May not be the end of ep collider physics… For now…we note that:
H1 in 2007 Took its last data on 30th June… …in the capable hands of experts from Liverpool…
…
H1 legacy to Liverpool: Knowledge Transfer via people… already soon
…including some with extremely useful skills: (The ‘Christmas Tree’ Nebula) Happy Christmas!