Hello. This is my webpage for the High Energy Physics Group at the University of Texas at Arlington.
I am currently in my forth year of graduate studies at UTA. I am a member of the DØ Collaboration at Fermilab.
I recently began working the the Stony Brook group, under the instruction of Paul Grannis,
continuing a Higgs search in the Standard Model channel H → eτ jj.
I also am responsible for the RunII tauID certification, working closely with Abid Patwa
and Fabrice Couderc. My academic advisor at UTA is
Andrew Brandt. We are also involved with laser testing of MCP-PMTs for an ATLAS upgrade.
Teaching
For the spring 2012 semester I will be the grader and final project instructor for Nuclear and Particle. You can find materials for the class here: Nuclear and_Particle
Current Work
DØ
The DØ Collaboration is a worldwide collaboration of over 80 universities and laboratories.
Our detector is a 5,000 ton general purpose detector. It collected data in two periods: RunI (1992-1996) where DØ along with
CDF discovered the top quark (the most massive Standard Model quark who's mass is roughly the
same as a gold nucleus!), and RunII (2001-2011). I am currently analyzing the 10fb-1 of data from RunII and plan to graduate in 2013.
The SM Higgs search H → eτ jj describes any process in which the final state is and electron
(e) coming from the hadronic decay of a τ, a τ
(which is reconstructed as a jet) and two jets (j). It is sensitive to three Higgs production processes: (1) associated production, (2) vector boson fusion,
and (3) gluon gluon fusion, and to Higgs decays to ττ, bb and WW.
There are a number of background processes which make it quite difficult to discern signal from background including multi-jets,
W/Z+ jets, and dibosons. To increase our signal to background ratio we employ boosted decision trees (BDT) which are trained to separate signal from background.
My service task to the collaboration has been to perform the tauID certification for the most current datasets.
The Monte Carlo (MC) simulation of our detector is not perfect, and its performace must be corrected based on observations of real data.
These corrections decrease the overal systematic uncertainties of any measurement that uses a tau, which include many prominent Higgs searches.
The plots for my tau certification can be found here: Tau_ID
ATLAS Forward Proton
A group of a dozen universities from several countries are proposing to build a detector specifically designed to detect forward
scattered protons originating from collisions in the center of the ATLAS detector at the Large Hadron Collider (LHC) in Geneva, Switzerland.
The proton detector system consists of a novel silicon tracking detector, and a precision time-of-flight counter.
The UTA group is leading the development of this time-of-flight detector (TOF).
Since August 2008 we have designed and implemented a series of lenses, filters, and mirrors that split the laser signal.
We focus the split laser beam on two different PMT channels and measure the time difference using a LeCroy 6 GHz oscilloscope.
This setup allows us to measure the response of the PMT as a function of high voltage and light intensity.
By isolating the individual components of the detector in this fashion we can fully characterize each device's response.
Laser-based tests of the PMT and electronics are on going. We recently had a test beam at CERN, and are currently working on analyzing that data. With this new information we plan to finalize our detector concept for installation at the LHC in 2014.
MINERνA
In fulfillment of my undergraduate senior research requirement I worked with Dr. Jeff Nelson
on the MINERνA Experiment. The goal of this experiment is to measure low energy neutrino interactions, in order to support neutrino oscillation
experiments and also to study the strong dynamics of the nucleon and nucleus that affect these interactions.
The high-energy group at William and Mary is currently analyzing data collected from MINERνA.
All components are functioning smoothly and quality physics results are constantly being produced.
Science Undergraduate Laboratory Internships
In Summer 2006 I participated in the SULI program
at TJNAF in Newport News, VA. Under the supervision of
Dr Harut Avagyan. Over a ten week period I analyzed the asymmetry in exclusive πo production.
We weres able to measure the asymmetry with good precision. The results of my research were later used as a baseline subtraction for
various studies conducted in Hall B at JLab.
Have you ever wondered about the phases of the moon? Extra solar planets? The origins of the universe? Well you're in luck. I am currently an educator of the UTA Planetarium . I have always had an interest in the stars and love to teach and discus these topics with just about anyone. Please come see me at the planetarium! Or if you have a burning question that can't wait, feel free to send me a mail.
The Physics Department at The University of Texas at Arlington
Ian Howley
