Ibérica magazine (1913-2004) and teh Ebro Observatory

Fa cent anys nasqué a l'Observatori de l'Ebre la revista de divulgació Ibérica, fruit de la idea i planificació de Ricard Cirera i Salse, S.J., fundador de l'Observatori de l'Ebre a Roquetes (Baix Ebre). Des del començament, Cirera va propugnar la importància de difondre el coneixements científic i tecnològic, i els avenços que s'hi anaven produint. La revista Ibérica va ser la manifestació del seu esforç i al llarg de la seva història va contribuir a la divulgació de la ciència i, per tant, a entendre millor el progrés científic al llarg del segle XX. Aquest treball pretén fer conèixer l'entorn que va envoltar aquest projecte —els antecedents històrics i la relació de la Companyia de Jesús amb la ciència i el Col·legi Màxim que s'establí a Tortosa— i el recorregut de la revista fins al seu acabament, l'any 2005.The popular science magazine Ibérica was founded at the Ebro Observatory 100 years ago. It was introduced and developed by Ricard Cirera i Salse, S.J., founder of the Ebro Observatory in Roquetes, at the Ebro Delta, southern Catalonia. From the start, Cirera advocated for the importance of spreading scientifi c and technological knowledge as well as the latest advances in these fi elds. The magazine Ibérica was the manifestation of his efforts. It contributed to the popularization of science throughout its history and thus to a better understanding of scientifi c progress over the course of the 20th century. The present work aims to shed light on the context and setting of the project—its historical background, the relationship of the Society of Jesus to science and to the Jesuit Col·legi Màxim in Tortosa—as well as the path covered by the magazine from its inception in 1913 until the end of the publication, in 2005

The HARP TPC laser calibration system

Abstract A novel apparatus for the calibration of the HARP Time Projection Chamber has been designed, developed and built. The apparatus consists of a large number of point-like photo-electron sources located at precise positions inside the detector volume. The photo-electron sources are optical quartz fibers on which one end is coated with an aluminum layer of ∼80 A thickness and are held in place on the high-voltage membrane. The fibers are used to guide UV laser light pulses that generate photoelectrons on the fiber tips acting as photo-electron emitters. The photo-electrons drift inside the detector and produce the calibration signals. The technique allows to assess E × B distortions and to measure drift velocity, ion feedback and time stability in real time