1,784 research outputs found
Integrated test environment for a part of the LHCb calorimeter - TWEPP09
An integrated test environment for the data acquisition electronics of the Scintillator Pad Detector (SPD) from the calorimeter of the LHCb experiment is presented. It allows to test separately every single board or to perform global system tests, while being able to emulate every part of the system and debug it. This environment is foreseen to test the production of spare electronic boards and help the maintenance of the SPD electronics along the life of the detector. The heart of the system is an Altera Stratix II FPGA while the main board can be controlled over USB, Ethernet or WiFi
Palbociclib Rechallenge for Hormone Receptor-Positive/HER-Negative Advanced Breast Cancer: Findings from the Phase II BioPER Trial
Hormone receptor; Advanced breast cancerCà ncer de mama avançat; Receptor hormonalCåncer de mama avanzado; Receptor hormonalPurpose:
To assess the efficacy and exploratory biomarkers of continuing palbociclib plus endocrine therapy (ET) beyond progression on prior palbociclib-based regimen in patients with hormone receptorâpositive/HER2-negative (HR+/HER2â) advanced breast cancer (ABC).
Patients and Methods:
The multicenter, open-label, phase II BioPER trial included women who had experienced a progressive disease (PD) after having achieved clinical benefit on the immediately prior palbociclib plus ET regimen. Palbociclib (125 mg, 100 mg, or 75 mg daily orally for 3 weeks and 1 week off as per prior palbociclib-based regimen) plus ET of physician's choice were administered in 4-week cycles until PD or unacceptable toxicity. Coprimary endpoints were clinical benefit rate (CBR) and percentage of tumors with baseline loss of retinoblastoma (Rb) protein expression. Additional endpoints included safety and biomarker analysis.
Results:
Among 33 patients enrolled, CBR was 34.4% [95% confidence interval (CI), 18.6â53.2; P < 0.001] and 13.0% of tumors (95% CI, 5.2â27.5) showed loss of Rb protein expression, meeting both coprimary endpoints. Median progression-free survival was 2.6 months (95% CI, 1.8â6.7). No new safety signals were reported. A signature that included baseline mediators of therapeutic resistance to palbociclib and ET (low Rb score, high cyclin E1 score, ESR1 mutation) was independently associated with shorter median progression-free survival (HR, 22.0; 95% CI, 1.71â282.9; P = 0.018).
Conclusions:
Maintaining palbociclib after progression on prior palbociclib-based regimen seems to be a reasonable, investigational approach for selected patients. A composite biomarker signature predicts a subset of patients who may not derive a greater benefit from palbociclib rechallenge, warranting further validation in larger randomized controlled trials.This work was supported by Pfizer. The authors would like to thank the patients, their caregivers, and their families for participating in this study and all investigators and site personnel. The BioPER study was conceived and designed by Medica Scientia Innovation Research (MEDSIR) in collaboration with Pfizer Inc., which funded the study and provided palbociclib. J. Albanell acknowledges CIBERONC CB16/12/00241, PI21/00002, funded by Instituto de Salud Carlos III (ISCIII) and co-funded by the European Union, Generalitat de Catalunya (2017 SGR 507)
Readout electronics for low dark count pixel detectors based on geiger mode avalanche photodiodes fabricated in conventional CMOS technologies for future linear colliders
The high sensitivity and excellent timing accuracy of Geiger mode avalanche photodiodes makes them ideal sensors as pixel detectors for particle tracking in high energy physics experiments to be performed in future linear colliders. Nevertheless, it is well known that these sensors suffer from dark counts and afterpulsing noise, which induce false hits (indistinguishable from event detection) as well as an increase of the necessary area of the readout system. In this work, we present a comparison between APDs fabricated in a high voltage 0.35 ”m and a high integration 0.13 ”m commercially available CMOS technologies that has been performed to determine which of them best fits the particle collider requirements. In addition, a readout circuit that allows low noise operation is introduced. Experimental characterization of the proposed pixel is also presented in this work
The Front End Electronics of the Scintillator Pad Detector of LHCb Calorimeter
In this paper the Front End electronics of the Scintillator Pad Detector (SPD) is outlined. The SPD is a sub-system of the Calorimeter of the LHCb experiment designed to discriminate between charged and neutral particles for the first level trigger. The system design is presented, describing its different functionalities implemented through three different cards and several ASICs. These functionalities are signal processing and digitization, data transmission, interface with control and timing systems of the experiment, low voltage power supply distribution and monitoring. Special emphasis is placed on installation and commissioning subjects such as cabling, grounding, shielding and power distribution
Belle II Technical Design Report
The Belle detector at the KEKB electron-positron collider has collected
almost 1 billion Y(4S) events in its decade of operation. Super-KEKB, an
upgrade of KEKB is under construction, to increase the luminosity by two orders
of magnitude during a three-year shutdown, with an ultimate goal of 8E35 /cm^2
/s luminosity. To exploit the increased luminosity, an upgrade of the Belle
detector has been proposed. A new international collaboration Belle-II, is
being formed. The Technical Design Report presents physics motivation, basic
methods of the accelerator upgrade, as well as key improvements of the
detector.Comment: Edited by: Z. Dole\v{z}al and S. Un
Opposite-side flavour tagging of B mesons at the LHCb experiment
The calibration and performance of the oppositeside
flavour tagging algorithms used for the measurements
of time-dependent asymmetries at the LHCb experiment
are described. The algorithms have been developed using
simulated events and optimized and calibrated with
B
+ âJ/ÏK
+, B0 âJ/ÏK
â0 and B0 âD
ââ
Ό
+
ΜΌ decay
modes with 0.37 fbâ1 of data collected in pp collisions
at
â
s = 7 TeV during the 2011 physics run. The oppositeside
tagging power is determined in the B
+ â J/ÏK
+
channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty
is statistical and the second is systematic
Measurement of the ratio of branching fractions BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma)
The ratio of branching fractions of the radiative B decays B0 -> K*0 gamma
and Bs0 -> phi gamma has been measured using 0.37 fb-1 of pp collisions at a
centre of mass energy of sqrt(s) = 7 TeV, collected by the LHCb experiment. The
value obtained is BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) = 1.12 +/- 0.08
^{+0.06}_{-0.04} ^{+0.09}_{-0.08}, where the first uncertainty is statistical,
the second systematic and the third is associated to the ratio of fragmentation
fractions fs/fd. Using the world average for BR(B0 -> K*0 gamma) = (4.33 +/-
0.15) x 10^{-5}, the branching fraction BR(Bs0 -> phi gamma) is measured to be
(3.9 +/- 0.5) x 10^{-5}, which is the most precise measurement to date.Comment: 15 pages, 1 figure, 2 table
Observation of two new baryon resonances
Two structures are observed close to the kinematic threshold in the mass spectrum in a sample of proton-proton collision data, corresponding
to an integrated luminosity of 3.0 fb recorded by the LHCb experiment.
In the quark model, two baryonic resonances with quark content are
expected in this mass region: the spin-parity and
states, denoted and .
Interpreting the structures as these resonances, we measure the mass
differences and the width of the heavier state to be
MeV,
MeV,
MeV, where the first and second
uncertainties are statistical and systematic, respectively. The width of the
lighter state is consistent with zero, and we place an upper limit of
MeV at 95% confidence level. Relative
production rates of these states are also reported.Comment: 17 pages, 2 figure
Observation of excited Lambda_b0 baryons
Using pp collision data corresponding to 1.0 fb-1 integrated luminosity
collected by the LHCb detector, two narrow states are observed in the
Lambda_b0pi+pi- spectrum with masses 5911.97 +- 0.12(stat) +- 0.02(syst) +-
0.66(Lambda_b0 mass) MeV/c^2 and 5919.77 +- 0.08(stat) +- 0.02(syst) +-
0.66(Lambda_b0 mass) MeV/c^2. The significances of the observations are 5.2 and
10.2 standard deviations, respectively. These states are interpreted as the
orbitally-excited Lambda_b0 baryons, Lambda_b*0(5912) and Lambda_b*0(5920).Comment: Replaced by version published in Phys. Rev. Lett, modified fit with
better mass resolution treatmen
Measurement of the CP-violating phase phi_s in the decay Bs->J/psi phi
We present a measurement of the time-dependent CP-violating asymmetry in B_s
-> J/psi phi decays, using data collected with the LHCb detector at the LHC.
The decay time distribution of B_s -> J/psi phi is characterized by the decay
widths Gamma_H and Gamma_L of the heavy and light mass eigenstates of the
B_s-B_s-bar system and by a CP-violating phase phi_s. In a sample of about 8500
B_s -> J/psi phi events isolated from 0.37 fb^-1 of pp collisions at sqrt(s)=7
TeV we measure phi_s = 0.15 +/- 0.18 (stat) +/- 0.06 (syst) rad. We also find
an average B_s decay width Gamma_s == (Gamma_L + Gamma_H)/2 = 0.657 +/- 0.009
(stat) +/- 0.008 (syst) ps^-1 and a decay width difference Delta Gamma_s ==
Gamma_L - Gamma_H} = 0.123 +/- 0.029 (stat) +/- 0.011 (syst) ps^-1. Our
measurement is insensitive to the transformation (phi_s,DeltaGamma_s --> pi -
phi_s, - Delta Gamma_s.Comment: 9 pages, 3 figure
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