The LHCb tracking system

The LHCb detector is being constructed to measure CP-violation parameters and rare B decays. The LHCb tracking system consists of silicon micro-strip detectors and straw chambers. The system is composed of four major sub-detectors: the Velo (Vertex Locator), TT (Trigger Tracker), IT (Inner Tracker) and OT (Outer Tracker). The Velo uses silicon micro-strip detectors which are placed at 8 mm from the beam, and that can be retracted during injection. The TT is a four-layer silicon strip detector that covers the full acceptance of the experiment at the entrance of the spectrometer dipole magnet. The fringe field of the magnet allows the transverse momentum of tracks to be measured by their deflection between the Velo and TT detectors for use in the trigger. The IT and OT detectors measure the tracks behind the magnet. The IT is a silicon strip detector which covers the region close to the beam pipe, while the OT is a straw tube detector which covers the rest of the acceptance. All of the detectors are currently under construction and will be ready for installation before the end of 2006. The expected performance for the tracking system is as follows; the tracking efficiency is larger than 95% and the ghost rate is smaller than 7%, for tracks with a momentum larger than 12 GeV. The momentum resolution ranges from 0.35% to 0.5% and the IP resolution reaches 14 mm for tracks with a large transverse momentum

Development of a radiation hard version of the Analog Pipeline Chip APC128

The Analog Pipeline Chip (APC) is a low noise, low power readout chip for silicon micro strip detectors with 128 channels containing an analog pipeline of 32 buffers depth. The chip has been designed for operation at HERA with a power dissipation of 300-400 muW per channel and has been used also in several other particle physics experiments. In this paper we describe the development of a radiation hard version of this chip that will be used in the H1 vertex detector for operation at the luminosity upgraded HERA machine. A 128 channel prototyping chip with several amplifier variations has been designed in the radiation hard DMILL technology and measured. The results of various parameter variations are presented in this paper. Based on this, the design choice for the final production version of the APC128-DMILL has been made.Comment: 10 pages, 10 figure

The Bs -> Ds pi and Bs -> Ds K selections

The decay channels Bs->Dspi and Bs->DsK will be used to extract the physics parameters $\Delta m_s$, $\Delta\Gamma_s$ and $\gamma + \phi_s$. Simulation studies based on Monte Carlo samples produced in 2004 and 2005 show that a total of 140k Bs->Dspi and 6.2k Bs->DsK events are expected to be triggered, reconstructed and selected in $2fb^{-1}$ of data ($10^7s$ of data taking at a luminosity of 2\times 10^{32}\unit{cm^{-2}s^{-1}}). The combinatorial background-over-signal ratio originating from inclusive bb events is expected to be $B/S Dspi whereas, for Bs->DsK, the limit is$B/S < 0.18~\at~90\%$~CL

Tuberculose in Nederland 2012

Op de gedrukte exemplaren van het rapport is het nummer 15000204. Het rapportnummer heeft een 0 te weinig; na versturing van de rapporten is dit pas opgemerktIn 2012 werden 958 patiënten met tuberculose gemeld aan het Nederlands Tuberculose Register (NTR). Dit komt overeen met een incidentie van tuberculose van 5,7 per 100.000 inwoners. Ten opzichte van 2011 en 2010 is de incidentie met respectievelijk vier procent en tien procent afgenomen. Sinds 2002 is het aantal tbc-patiënten in Nederland met 32% gedaald. In 2012 werd bij 53 procent van de gemelde patiënten longtuberculose geconstateerd. Het aantal patiënten met longtuberculose (pulmonale tbc) daalt sneller dan het aantal met extrapulmonale tbc (tuberculose buiten de longen). Het percentage extrapulmonale gevallen was het hoogste onder tbc-patiënten die in het buitenland zijn geboren. De meest voorkomende vorm van extrapulmonale tuberculose was tuberculose van de perifere lymfklieren. Achttien procent (177) van de tbc-patiënten in 2012 had sputumpositieve longtuberculose, de meest besmettelijke vorm van tuberculose. De incidentie van sputumpositieve longtuberculose in 2012 was 1,1 per 100.000 inwoners. Tuberculose komt in Nederland vaker voor bij personen geboren in het buitenland (eerstegeneratieallochtonen) en tweedegeneratieallochtonen. Bijna drie kwart van het aantal tbc-patiënten in 2012 was geboren in het buitenland (73%). Van de groep eerstegeneratieallochtonen met tuberculose in Nederland was de groep Somaliërs net als voorgaande jaren het grootste (170). Het percentage tbc-patiënten afkomstig uit Somalië was daarmee even groot als het percentage autochtone Nederlanders met tuberculose (18 procent), maar de incidentie onder Somaliërs in Nederland is bijna 500 maal hoger dan onder autochtone Nederlanders (respectievelijk 1,3 en 691 per 100.000 inwoners). Multiresistente tuberculose Het aantal patiënten met multiresistente tuberculose (MDR-tbc) in Nederland schommelt de laatste vijf jaar tussen tien en twintig patiënten; dat is 1-2% van het totaal aantal patiënten. In 2012 werden elf patiënten met multiresistente tuberculose gediagnosticeerd. Eén van de elf patiënten met mulitresistente tuberculose was afkomstig uit Nederland, de tien andere patiënten uit het buitenland. Resultaat van de behandeling Van alle in 2011 geregistreerde tbc-patiënten voltooide 87% de tbc-behandeling met succes. Bij nieuwe patiënten met longtuberculose was dit percentage iets lager (85%). Patiënten met multiresistente tuberculose voltooiden minder vaak de behandeling. Van de elf MDR-tbc-patiënten gediagnosticeerd in 2010 voltooiden zeven (64%) de behandeling met succes, één patiënt (9%) brak de behandeling voortijdig af, één patiënt zette de behandeling in het buitenland voort, één patiënt is overleden aan een andere oorzaak dan tuberculose en van één patiënt is het behandelresultaat (nog) niet bekend. Sterfte aan tuberculose Van de tbc-patiënten geregistreerd in het NTR in 2011 en 2012 overleden respectievelijk achttien (1,8%) en zes personen (0,6%) aan tuberculose. Patiënten met ernstige comorbiditeit hebben grotere kans op sterfte aan tuberculose. In 2012 overleed één persoon met diabetes, twee personen met een maligniteit en één persoon met nierinsufficiëntie aan tuberculose. Latente tbc-infectie (LTBI) In 2012 zijn 1.293 nieuwe gevallen van LTBI geregistreerd. Bij 855 personen werd de diagnose bij bron- en contactonderzoek vastgesteld. In 2011 startten in totaal 1.027 van de 1.297 personen (79%) een preventieve behandeling. Van hen voltooide 84% de LTBI-behandeling met succes. Delay Op grond van de gegevens in het NTR is de gemiddelde duur van het diagnostisch delay in de periode 2005-2012 niet toegenomen, hoewel bij illegalen, dak- en thuislozen, en drugs- en alcoholverslaafden wel aanwijzingen zijn voor een langer patient delay. Bij ruim een kwart van de patiënten die passief worden gevonden is wel sprake van een 'te lang' of 'ongunstig delay'. Voor doctor delay geldt hetzelfde: er is bij ruim een kwart van de patiënten die passief worden gevonden sprake van een 'te lang' of 'ongunstig delay'. Case finding In totaal 15% van alle tbc-patiënten werd in 2012 gevonden door actieve opsporing door de afdeling tbc-bestrijding van de GGD. Het percentage tbc-patiënten dat gevonden wordt door screening van risicogroepen zoals nieuwe immigranten, asielzoekers, drugsverslaafden en dak- en thuislozen neemt al langere tijd af. In de jaren 1993-1998 werd 14% van de tbc-patiënten gevonden door screening, maar in 2012 was dit nog maar 8%. Het percentage patiënten gevonden via bron- en contactonderzoek was in 2012 hetzelfde als in voorgaande jaren (7%). Tbc-patiënten met verminderde weerstand Het percentage tbc-patiënten met een co-infectie met hiv was 3% in 2012. Het percentage tbc-patiënten die op co-infectie met hiv werden getest nam toe van 28% in 2008 naar 49% in 2011, maar is in 2012gestagneerd (47%). Van patiënten uit risicogebieden zoals sub-Sahara Afrika was in 59% van de gevallen de hiv-status bekend. Het aantal tbc-patiënten die behandeld worden met TNF-alfaremmers neemt toe. In 2012 betrof het achttien (1,9%) patiënten. Transmissie en clustersurveillance Van de patiënten met kweekpositieve tuberculose clusterde de helft met een voorgaande patiënt. Bij een derde van de clusterende patiënten was sprake van recente clustering, een mogelijk gevolg van recente transmissie in Nederland. In 2012 vertoonden vier van de clusters een groei van meer dan vijf patiënten. De laatste jaren zijn er minder snelgroeiende clusters, een teken dat transmissie van M. tuberculosis in Nederland afneemt of dat de bestrijdingsmaatregelen effectief zijn.In 2012 958 cases of tuberculosis (TB) were reported to the Netherlands Tuberculosis Register (NTR). The incidence rate was 5.7 per 100,000 population. Since 2002 the number of TB patients in the Netherlands declined with 32%. In 2012 53% of the notified cases was diagnosed with pulmonary tuberculosis. Over the years the number of patients with extrapulmonary TB declined less than the number with pulmonary TB. The percentage extrapulmonary cases is highest among foreign-born TB patients. Tuberculosis of the extra thoracic lymph nodes is the most common site of disease in extrapulmonary cases. 18% (177) of all TB cases in 2012 was sputum-smear positive. The incidence rate of smear-positive pulmonary TB was 1.1 per 100,000 population. The majority of TB patients in the Netherlands was foreign-born (73%). As in previous years the largest population group with TB in 2012 was Somalian (170). The percentage of TB patients born in Somalia is in 2012 the same as the percentage native Dutch TB patients (18%). The incidence rate among people coming from Somalia is almost 500 times higher than the incidence rate of the native Dutch population (respectively 691 and 1.3 per 100,000 population). Multidrug-resistant tuberculosis In the last five years the number of patients with multidrug-resistant tuberculosis (MDR-TB) in the Netherlands varies between ten and twenty patients, 1-2% of the total number of TB patients. In 2012 eleven patients with MDR-TB were registered; ten were foreign-born. Treatment Outcome In 2011 87% of all TB patients completed treatment successfully. Of new cases with pulmonary TB 85% completed treatment successfully. Patients with MDR-TB completed treatment less often. Seven (64%) out of eleven MDR-TB-patients diagnosed in 2010 completed treatment successfully, one patient (9%) interrupted treatment, one patient continued treatment abroad, one patient died due to another cause than tuberculosis and of one patient treatment outcome is (still) unknown. TB-patients with co-morbidity or immune disorders The percentage of hiv-infected TB patients was 3% in 2012. The percentage TB patients tested for hiv increased from 28% in 2008 to 49% in 2011, but did not increase in 2012 (47%). Hiv-status was known in 59% of TB patients coming from sub-Saharan Africa, a hiv endemic area. The number of TB patients associated with TNF-alfa inhibitors treatment increases. In 2012 18 patients were registered (1.9%). Tuberculosis deaths Respectively 18 (1.8%) and 6 (0.6%) TB patients in 2011 and 2012 died due to tuberculosis. TB patients with serious co-morbidity have a higher risk of dying. In 2012 one person with diabetes, two persons with cancer and one person with renal insufficiency died due to tuberculosis. Respectively 20 (2.0%) and 20 (2.1%) TB patients in 2011 and 2012 died of other causes. Latent Tuberculosis Infection (LTBI) In 2012 1,293 new cases of LTBI were reported. 855 of these cases were detected through contact investigation. In 2011 1,027 of 1,297 cases (79%) started preventive treatment. Eighty-four percent of all persons with LTBI who received preventive treatment completed treatment successfully. Delay The mean length of the diagnostic delay over the years 2005-2012 did not increase, although undocumented TB patients, homeless TB patients, and drug and alcohol addicts with TB are associated with a longer patient delay. In more than a quarter of the passively detected cases a too long or 'unfavorable' patient delay was registered. This also applies to doctor delay; in more than a quarter of the passively detected cases a too long or 'unfavorable' delay was registered. Case finding Fifteen percent of all TB patients was detected by active case finding by the TB department of the Municipal Health Services. The percentage TB patients detected through screening of risk groups such as new immigrants, asylum seekers, drug addicts and homeless people has been decreasing for some time; in the years 1993-1998 14% of all TB patients was detected through screening, in 2012 only 8%. The number and percentage of cases found through contact investigation stayed more or less the same (7%). Transmission and cluster surveillance In 2012 50% of the cases with a positive culture belonged to a cluster. In one third of these cases recent clustering was registered, possibly as a result of recent transmission in the Netherlands. In 2012 four existing clusters showed growth of more than five patients. In the last few years there were no large outbreaks registered in the Netherlands

Geodynamics, 3rd edn

Turcotte, D.L. and Schubert, G., eds, Cambridge University Press, 2014, ISBN: 9780521186230, Paperback, 636 pp. Turcotte and Schubert's ‘Geodynamics’ book has been essential reading for generations of Earth scientists. Ever since the appearance of the first edition in 1982, lecturers in geodynamics worldwide use the book as reading material, and the large number of citations in the scientific literature illustrates that the book is also heavily used by researchers. I still remember well the excitement when I bought the 2nd edition when it became available a little more than a decade ago: after years of taking out well-worn copies from the University library, I suddenly was the proud owner of my own copy (which by now is equally well worn). Over the years, the book has helped me to understand and teach many different aspects of geodynamics, and it continues to do so. Now the 3rd edition lies in front of me. A first leafing-through shows that most of the familiar contents is much the same. Apart from being a bit bulkier than the previous edition, the structure and basic contents of first 10 chapters remained mostly unchanged, with the same wide range of geodynamic topics presented in the same convenient, familiar way: Chapter 1 sets the scene, describes the plate-tectonic framework,

New insight in the Hawaiian plume swell dynamics from scaling laws

The formation and shape variation of the Hawaiian plume swell is re-examined numerically. Scaling laws for the plume buoyancy flux and swell width and height help gaining new insight in relationships between swell formation and relevant model parameters, like plume temperature and size, and mantle rheology. A scaling law for the plume buoyancy F = Aη0 −1.2 R p 3.5ΔT p 2.2 exp(1.3 × 10−8 EΔT p ), with background mantle viscosity η0, plume radius R p , plume excess temperature ΔT p , and activation energy E fits numerical flux measurements within 8%. Scaling laws for the swell width and height have similar forms, and their multiplication resembles the buoyancy flux scaling law within 10%. These scaling laws suggest that the background mantle viscosity plays a significant role, and that the increased Hawaiian plume intensity ∼25 Ma ago is due to a plume excess temperature increase of 50%

Repeat ridge jumps associated with plume‐ridge interaction, melt transport, and ridge migration

Repeated shifts, or jumps, of mid-ocean ridge segments toward nearby hot spots can produce large, long-term changes to the geometry and location of the tectonic plate boundaries. Ridge jumps associated with hot spot–ridge interaction are likely caused by several processes including shear on the base of the plate due to expanding plume material as well as reheating of lithosphere as magma passes through it to feed off-axis volcanism. To study how these processes influence ridge jumps, we use numerical models to simulate 2-D (in cross section) viscous flow of the mantle, viscoplastic deformation of the lithosphere, and melt migration upward from the asthenospheric melting zone, laterally along the base of the lithosphere, and vertically through the lithosphere. The locations and rates that magma penetrates and heats the lithosphere are controlled by the time-varying accumulation of melt beneath the plate and the depth-averaged lithospheric porosity. We examine the effect of four key parameters: magmatic heating rate of the lithosphere, plate spreading rate, age of the seafloor overlying the plume, and the plume-ridge migration rate. Results indicate that the minimum value of the magmatic heating rate needed to initiate a ridge jump increases with plate age and spreading rate. The time required to complete a ridge jump decreases with larger values of magmatic heating rate, younger plate age, and faster spreading rate. For cases with migrating ridges, models predict a range of behaviors including repeating ridge jumps, much like those exhibited on Earth. Repeating ridge jumps occur at moderate magmatic heating rates and are the result of changes in the hot spot magma flux in response to magma migration along the base of an evolving lithosphere. The tendency of slow spreading to promote ridge jumps could help explain the observed clustering of hot spots near the Mid-Atlantic Ridge. Model results also suggest that magmatic heating may significantly thin the lithosphere, as has been suggested at Hawaii and other hot spots