D0 work

This page is almost done. These days I wonder if it will ever be finished, it was all so long ago. And now the Tevatron will be shut down anyway. It had a good run (actually two) though.

I was a member of the D0 experiment at Fermilab between 1999 and 2008.
Below is a short summary of the work I did during this time.

Here is the official description of the RunII D0 detector: "The Upgraded DØ Detector",
Nucl. Instrum. Methods in Phys. Res. A 565, 463 (2006), physics/0507191 (warning: BIG file!)

My contributions

Level 3
Together with Rick Jesik, I was the convener (read the person who fixed all the bugs nobody else could handle) of the Level 3 trigger group between 2005 and 2008. The last update of the Level 3 webpage probably dates from this time.

Higgs Searches
I worked on Higgs searches in the channel h -> b bbar. Please see D0 Notes 5726 and 5709.

Clued0-admin
I was a clued0-admin, that means I tried to help administering a 300+ machines decidedly non-homogeneous linux cluster. Voluntarily.

Level 3 Muons
I used to look after the Level 3 muons. Now Nirmalya Parua has taken over this job. My work is summarized in the following two notes:
Note 4470 and Note 4887. To make my life easier I wrote a package, called l3muo_cert which makes all kinds of quality monitoring plots (with a bit of prodding it can find J/Psi too !). I even wrote some documentation: L3 Muon page

b-physics trigger
I was the trigger representative for the b-physics group (for triggerlists v13, v14 and the beginning of v15). I developed new triggers using available tools, monitored the performance of current triggers, kept an eye on the rates and prescales and negotiated the b-physics quotas in the trigger board. I also worked as a crash test dummy for the trigger simulation (read: run and debug) and assisted my fellow collaborators with their trigger related problems. For further information, please refer to the b-physics trigger webpage.

Upsilon production at D0
Together with Andrzej Zieminski⁺ and Jundong Huang I am one of the main authors of the Run II Upsilon(1S) production cross-section measurement. The paper has been published by PRL (Phys. Rev. Lett. {94}, 232001 (2005)).
Questions by the collaboration regarding this paper were answered here.
⁺Andrzej (best boss I ever had) sadly died on Nov 1st 2007. Here is the obituary.

Publications

To date the D0 the experiment has published 132 papers on which I am an author. Here is a link to the official D0 publications webpage. Of these publications listed below are those where I have been directly involved.

I am one of the main authors of "Measurement of inclusive differential cross sections for Upsilon(1S) production in pbar p collisions at sqrt(s) = 1.96 TeV", Phys. Rev. Lett. 94, 232001 (2005).

Between 2004 to 2007 I reviewed the following analyses as a member of the D0 Editorial Board for lifetime measurements with a J/psi in the final state:

Measurement of the B_s^0 Lifetime in the Exclusive Decay Channel B_s^0 -> J/psi phi, Phys. Rev. Lett. 94, 042001 (2005)
Measurement of the Lambda_b Lifetime in the Decay Lambda_b -> J/psi Lambda with the D0 Detector Phys. Rev. Lett. 94, 102001 (2005)
Measurement of the lifetime difference in the B_s system, Phys. Rev. Lett. 95 , 171801 (2005)
Study of the Decay B_s -> Ds(*) Ds(*), PRL 99, 241801 (2007)
Measurement of the Lambda_b lifetime in the exclusive decay to J/psi Lambda, PRL 99, 142001 (2007)

During 2007-2008 I was a member of the D0 Editorial Board for Quarkonia and b-production, reviewing the following analysis submitted for publication:
Measurement of the polarization of the Upsilon(1S) and Upsilon(2S) states in collisions at sqrt(s)=1.96 TeV, Phys. Rev. Lett. 101, 182004 (2008)

In my position as b-physics trigger representative I have directly contributed to First Direct Limits on the B_s^0 Oscillation Frequency, Phys. Rev. Lett. 97 , 021802 (2006), which was the most cited HEP publication in 2006.

Conference Talks

CKM 2008:	Talk	Proceedings (unpublished)
Beauty 2006:	Talk	B Physics and Triggers at D0 - Operational Experience, Beauty 2006, Oxford, United Kingdom, Nucl. Phys. B (Proc. Suppl.) 170 (2007)
Beauty 2005:	Talk	b-quark and Upsilon(1S) production at the Tevatron, Beauty 2005, Assisi, Italy, Nucl. Phys. B (Proc. Suppl.) 156 (2006)
ISMD 2004:	Talk	Top and b physics at the Tevatron, ISMD 2004, Acta Physica Polonica B, Vol. 36, No. 2, (2005)
Pheno 2004:	Talk	No proceedings.
HCP 2002:	Talk	14th topical conference for Hadron Collider Physics, HCP 2002, Springer (2003)

Internal Publications (D0 Notes)

D0 Note 5726, Search for neutral Higgs bosons in multi-b-jet events in ppbar collisions at sqrt{s} = 1.96 TeV
D0 Note 5709, Search for neutral Higgs bosons in phi b -> bbb using RunIIb data
D0 Note 4887, p17 certification for Level 3 muons
D0 Note 4881, Mixing in the Bs System Using Bs to Ds Mu X ...
D0 Note 4863, A search for B_s oscillations at D0 ...
D0 Note 4470, p16 certification for Level 3 muons
D0 Note 4287, Software for the new muon scintillators
D0 Note 4266, Top mass measurement, Moriond 2003
D0 Note 4262, Upsilon cross-section
D0 Note 3822, Level 3 SMT clustering
D0 Note 3779, L3 CFT tracking

My thesis: A study of Bs -> J/Psi Phi in the D0 experiment and an example of HEP technology transfer,
Imperial College 2002 (gzipped ps)