4,419 research outputs found
Drift Chamber Alignment using Cosmic Rays
The Collider Detector at Fermilab (CDF) is a general-purpose experimental
apparatus with an inner tracking detector for measuring charged particles,
surrounded by a calorimeter for measurements of electromagnetic and hadronic
showers, and a muon detector system. We present a technique for, and results
of, a precise relative alignment of the drift chamber wires of the CDF tracker.
This alignment has been an important component of the track momentum
calibration, which is the basis for the charged-lepton calibration for the
measurement of the W boson mass at CDF
Premature harvesting of wild Musli (Chlorophytum borivilianum, Baker) and its impact on raw material quality: A case of Katni forest division, Madhya Pradesh
Katni is a major raw medicinal plant market of Central India. An attempt has been made to find out prevalent harvesting method of Musli (Chlorophytum borivilianum) and visual inspection of raw (dry) market samples collected from Katni market. Musli tubers were found adulterated both intentionally and unintentionally by various stakeholders in the market. The stakeholders adopted malpractices like selling similar looking C. tuberosum, C. arundinaceum species of musli along with genuine (C. borivilianum) material and occasionally dried roots of different species. Major reasons for poor quality in the study area are premature root harvesting, mis-identification of species, mixing of similar looking species etc. The study recommends that harvesting should be done after maturation (November) and awareness about species identification, processing among various stakeholders is required
Trans-scaphoid dislocation of the proximal row: a case report
This report is of a 32 year old man who presented with complains of pain, swelling and deformity of right wrist of four weeks duration. He gave history of road traffic accident four weeks back leading to injury to right wrist; Preoperative radiographs and C.T. scan images were suggestive of trans-scaphoid dislocation of the proximal row of wrist. A volar and dorsal approach were used to reduce this complex dislocation but was not successful. Wrist arthodesis was performed after doing proximal row carpectomy. One year follow-up of the patient showed fair result with grip strength of 85% to contralateral side and modified Mayo wrist score of 65 at one year.Key words: Trans-scaphoid dislocation, CT scan, carpectomy, wrist scor
Giant lipoma: an unusual cause of carpal tunnel syndrome
Carpal tunnel syndrome, in its idiopathic form, is an extremely common entrapment neuropathy in the clinical practice however secondary compressive causes are rare. Among secondary causes, tumors are even rarer. Although lipomas are the most common soft tissue tumor in the body, <5% of the benign tumors of the hand are lipomas. A 48-year old manual laborer man presented to us with a two-year history of numbness, tingling and burning pain in the palmar surface of the left hand and fingers along with a progressively increasing swelling in the hand and wrist. His medical history was unremarkable and no trauma episode was reported. According to the clinical examination and the result of median nerve conduction study (NCS) the diagnosis of carpal tunnel syndrome was established. Operative release of the transverse carpal ligament was subsequently performed along with excision of the lipoma using extensile open approach. Intraoperatively, median nerve and its digital branches were found to be stretched over the giant lipoma causing substantial compression to median nerve. Histopathological findings of the resected mass were consistent with lipoma. After two years the patient was pain-free without any sign of tumor recurrence. Lipomas are infrequently seen in hand and wrist, however giant lipoma as a cause of secondary carpal tunnel syndrome is even more rare, which makes this case interesting.Key words: Lipoma, carpal tunnel syndrome, median nerve, nerve compressio
Ewing's Sarcoma of the Sacroiliac Joint Presenting as Tubercular Sacroiliitis: A Diagnostic Dilemma
We report a case of Ewing's sarcoma of the sacroiliac joint in a 21-year-old male mimicking tubercular sacroiliitis, a rare entity not reported in literature. He presented with pain in the lower back radiating to the right lower limb along with constitutional symptoms of 3 months duration. On examination, the right sacroiliac joint was tender. The laboratory investigations showed anaemia, leukocytosis and raised erythrocyte sedimentation rate. On X-ray, features of right sacroiliitis were seen. This was further investigated with magnetic resonance imaging (MRI), which showed features consistent with tubercular sacroiliitis. Patient was then started on antitubercular treatment, but the improvement was not consistent. So, a contrast MRI was done, which indicated features of primary sarcoma. It was then further confirmed by a computed tomography-guided biopsy, which showed features consistent with Ewing's sarcoma of the sacroiliac joint
Search for TeV -rays from H1426+428 during 2004-07 with the TACTIC telescope
The BL Lac object H1426+428 () is an established source of TeV
-rays and detections of these photons from this object also have
important implications for estimating the Extragalactic Background Light (EBL)
in addition to the understanding of the particle acceleration and -ray
production mechanisms in the AGN jets. We have observed this source for about
244h in 2004, 2006 and 2007 with the TACTIC -ray telescope located at
Mt. Abu, India. Detailed analysis of these data do not indicate the presence of
any statistically significant TeV -ray signal from the source
direction. Accordingly, we have placed an upper limit of
on the integrated
-ray flux at 3 significance level.Comment: 11 pages, 5 figures accepted for publication in Journal of Physics G:
Nuclear and Particle Physic
Data processing model for the CDF experiment
The data processing model for the CDF experiment is described. Data
processing reconstructs events from parallel data streams taken with different
combinations of physics event triggers and further splits the events into
datasets of specialized physics datasets. The design of the processing control
system faces strict requirements on bookkeeping records, which trace the status
of data files and event contents during processing and storage. The computing
architecture was updated to meet the mass data flow of the Run II data
collection, recently upgraded to a maximum rate of 40 MByte/sec. The data
processing facility consists of a large cluster of Linux computers with data
movement managed by the CDF data handling system to a multi-petaByte Enstore
tape library. The latest processing cycle has achieved a stable speed of 35
MByte/sec (3 TByte/day). It can be readily scaled by increasing CPU and
data-handling capacity as required.Comment: 12 pages, 10 figures, submitted to IEEE-TN
Very High Energy gamma-ray observations of Mrk 501 using TACTIC imaging gamma-ray telescope during 2005-06
In this paper we report on the Markarian 501 results obtained during our TeV
-ray observations from March 11 to May 12, 2005 and February 28 to May
7, 2006 for 112.5 hours with the TACTIC -ray telescope. During 2005
observations for 45.7 hours, the source was found to be in a low state and we
have placed an upper limit of 4.62 10 photons cm
s at 3 level on the integrated TeV -ray flux above 1 TeV
from the source direction. However, during the 2006 observations for 66.8h,
detailed data analysis revealed the presence of a TeV -ray signal from
the source with a statistical significance of 7.5 above
1 TeV. The time averaged differential energy spectrum of the
source in the energy range 1-11 TeV is found to match well with the power law
function of the form () with and .Comment: 16 pages and 8 Figures Accepted for publication in the Journal of
Physics
Observations of TeV gamma-rays from Mrk 421 during Dec. 2005 to Apr. 2006 with the TACTIC telescope
The TACTIC -ray telescope has observed Mrk 421 on 66 clear nights
from Dec. 07, 2005 to Apr. 30, 2006, totalling 202 hours of on-source
observations. Here, we report the detection of flaring activity from the source
at 1 TeV energy and the time-averaged differential -ray spectrum
in the energy range 1-11 TeV for the data taken between Dec. 27, 2005 to Feb.
07, 2006 when the source was in a relatively higher state as compared to the
rest of the observation period. Analysis of this data spell, comprising about
97h reveals the presence of a -ray signal with
daily flux of 1 Crab unit on several days. A pure power law spectrum with
exponent as well as a power law spectrum with an exponential
cutoff and are found to provide
reasonable fits to the inferred differential spectrum within statistical
uncertainties. We believe that the TeV light curve presented here, for nearly 5
months of extensive coverage, as well as the spectral information at
-ray energies of 5 TeV provide a useful input for other groups
working in the field of -ray astronomy.Comment: 13pages,4figures; Accepted for publication in Astroparticle Physic
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