The latest T2K neutrino oscillation results

T2K is a long-baseline neutrino oscillation experiment taking data since 2010. A neutrino beam is produced at the J-PARC accelerator in Japan and is sampled at a Near Detector complex 280 m from the neutrino production point and at the far detector, Super-Kamiokande, located 295 km from the source. Beams predominantly composed of muon neutrinos or muon anti-neutrinos have been produced by changing the currents in the magnetic focusing horns. This presentation will show the most recent T2K oscillation results obtained from a combined analysis of the entire available data set in the muon neutrino and muon anti-neutrino disappearance channels, and in the electron neutrino and electron anti-neutrino appearance channels. The data cover runs 1 to 8 (2010 to 2017) and consist of $7.252 \cdot 10^{20}$ POT in neutrino mode and $7.531 \cdot 10^{20}$ POT in antineutrino mode. Using these data, we measure four oscillations parameters: $\sin^2 \theta_{23}$, $\sin^2 \theta_{13}$, $\Delta m_{32}^2$ and $\delta_{CP}$. The analysis excludes CP-conservation in the neutrino sector at 90\% C.L.Comment: 6 pages, 7 figures, 3 tables, proceeding of the EPS-HEP 2017 conferenc

A mid-IR survey of the L 1641-N region with ISOCAM

We present an analysis of the L 1641 outflow region using broad-band and narrow-band imaging data at mid-infrared wavelengths from ISOCAM. We detect a total of 34 sources in the $7.65^{\prime}$ x $8.40^{\prime}$ region covered by the broad-band filters. Four of these sources have no reported detection in previous studies of the region. We find that the source previously identified as the near-IR counter-part to the IRAS detected point-source (IRAS 05338-0624) is not the brightest source in the wavelength region of the IRAS 12 \micron\ filter. We find instead that a nearby object (within the beam of IRAS and not detected at near-IR wavelengths) outshines all others sources in the area by a factor of $\sim$2. We submit that this source is likely to be the IRAS detected point source. A comparison of the near-IR (J-H vs H-K) and mid-IR (J-K vs [6.7 um]-[14 um]) color-color plots shows only four sources with excess emission at near-IR wavelengths, but atleast 85% of all sources show excess emission at mid-IR wavelengths. The CVF spectra suggest a range of evolutionary status in the program stars ranging from embedded YSOs to the young disks. When combined with optical and near-IR age estimates, these results show active current star-formation in the region that has been on-going for at least 2 Myr.Comment: Submitted to ApJ. Abstracted edited for arXiv submission Replaced by version accepted by Ap

Search for short baseline nu(e) disappearance with the T2K near detector

8 pages, 6 figures, submitted to PRD rapid communication8 pages, 6 figures, submitted to PRD rapid communicationWe thank the J-PARC staff for superb accelerator performance and the CERN NA61 collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC and CFI, Canada; Commissariat `a l’Energie Atomique and Centre National de la Recherche Scientifique–Institut National de Physique Nucle´aire et de Physique des Particules, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; Russian Science Foundation, RFBR and Ministry of Education and Science, Russia; MINECO and European Regional Development Fund, Spain; Swiss National Science Foundation and State Secretariat for Education, Research and Innovation, Switzerland; STFC, UK; and DOE, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK. In addition participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; DOE Early Career program, USA

A Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande

Document submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresHyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger than that of Super-Kamiokande. One of the main goals of Hyper-Kamiokande is the study of $CP$ asymmetry in the lepton sector using accelerator neutrino and anti-neutrino beams. In this document, the physics potential of a long baseline neutrino experiment using the Hyper-Kamiokande detector and a neutrino beam from the J-PARC proton synchrotron is presented. The analysis has been updated from the previous Letter of Intent [K. Abe et al., arXiv:1109.3262 [hep-ex]], based on the experience gained from the ongoing T2K experiment. With a total exposure of 7.5 MW $\times$ 10$^7$ sec integrated proton beam power (corresponding to $1.56\times10^{22}$ protons on target with a 30 GeV proton beam) to a $2.5$-degree off-axis neutrino beam produced by the J-PARC proton synchrotron, it is expected that the $CP$ phase $\delta_{CP}$ can be determined to better than 19 degrees for all possible values of $\delta_{CP}$, and $CP$ violation can be established with a statistical significance of more than $3\,\sigma$ ($5\,\sigma$) for $76$ ($58$) of the $\delta_{CP}$ parameter space

Measurement of νˉμ\bar{\nu}_{\mu} and νμ\nu_{\mu} charged current inclusive cross sections and their ratio with the T2K off-axis near detector

We report a measurement of cross section $\sigma(\nu_{\mu}+{\rm nucleus}\rightarrow\mu^{-}+X)$ and the first measurements of the cross section $\sigma(\bar{\nu}_{\mu}+{\rm nucleus}\rightarrow\mu^{+}+X)$ and their ratio $R(\frac{\sigma(\bar \nu)}{\sigma(\nu)})$ at (anti-)neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K $\bar{\nu}/\nu$-flux, for the detector target material (mainly Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory frame kinematics of $\theta_{\mu}$500 MeV/c. The results are $\sigma(\bar{\nu})=\left( 0.900\pm0.029{\rm (stat.)}\pm0.088{\rm (syst.)}\right)\times10^{-39}$ and $\sigma(\nu)=\left( 2.41\ \pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}$in units of cm$^{2}$/nucleon and$R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)= 0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure

Measurements of neutrino oscillation in appearance and disappearance channels by the T2K experiment with 6.6 x 10(20) protons on target

111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee commentsWe thank the J-PARC staff for superb accelerator performance and the CERN NA61/SHINE Collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC, and CFI, Canada; CEA and CNRS/IN2P3, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; RSF, RFBR and MES, Russia; MINECO and ERDF funds, Spain; SNSF and SER, Switzerland; STFC, UK; and the U. S. Deparment of Energy, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK, and the Emerald High Performance Computing facility in the Centre for Innovation, UK. In addition, participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; and DOE Early Career program, USA

Measurement of the electron neutrino charged-current interaction rate on water with the T2K ND280 pi(0) detector

10 pages, 6 figures, Submitted to PRDhttp://journals.aps.org/prd/abstract/10.1103/PhysRevD.91.112010© 2015 American Physical Society11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PR

Reduction Algorithms for the Multiband Imaging Photometer for Spitzer

We describe the data reduction algorithms for the Multiband Imaging Photometer for Spitzer (MIPS) instrument. These algorithms were based on extensive preflight testing and modeling of the Si:As (24 micron) and Ge:Ga (70 and 160 micron) arrays in MIPS and have been refined based on initial flight data. The behaviors we describe are typical of state-of-the-art infrared focal planes operated in the low backgrounds of space. The Ge arrays are bulk photoconductors and therefore show a variety of artifacts that must be removed to calibrate the data. The Si array, while better behaved than the Ge arrays, does show a handful of artifacts that also must be removed to calibrate the data. The data reduction to remove these effects is divided into three parts. The first part converts the non-destructively read data ramps into slopes while removing artifacts with time constants of the order of the exposure time. The second part calibrates the slope measurements while removing artifacts with time constants longer than the exposure time. The third part uses the redundancy inherit in the MIPS observing modes to improve the artifact removal iteratively. For each of these steps, we illustrate the relevant laboratory experiments or theoretical arguments along with the mathematical approaches taken to calibrate the data. Finally, we describe how these preflight algorithms have performed on actual flight data.Comment: 21 pages, 16 figures, PASP accepted (May 2005 issue), version of paper with full resolution images is available at http://dirty.as.arizona.edu/~kgordon/papers/PS_files/mips_dra.pd