MIRROR Issue 4 April 2016

NEWSletter April 2016

Issue 4 In this Issue • News from FAIR • New Study confirms Antihydrogen Charge is Neutral • News in Short • Positions Vacancies • Selected Events

Antihydrogen charge, LEAP and a new Collaboration Member, The Extra Low Energy Antiproton ring (ELENA) will be a critical upgrade to the unique AD facility and will be commissioned from summer 2016. This new ring will significantly enhance the beam quality and enable new experiments.

In order to fully exploit the discovery potential of ELENA and to pave the way for a vibrant long-term physics program with low energy antiprotons, advances are required in a number of research areas: This includes beam handling and cooling, advanced diagnostics tools, as well as advanced experimental techniques for improved precision and novel experiments that exploit the improved beam quality that these decelerators can provide. It was interesting to see how much of this has happened recently in all these areas through talks and posters at the LEAP conference that took place in Japan last month. This newsletter edition will give you a short summary of this main event for our community, as well as an overview of recent papers, open positions and upcoming events. It also presents a new collaboration member. Enjoy !

With our very best wishes Carsten, Thomas and Jochen

News from FAIR As of 1st February 2016, Jörg Blaurock is the first joint Technical Managing Director of FAIR and GSI. Prior to this he has been working in international large-scale plant construction for over 20 years, overseeing full planning, delivery, assembly and commissioning of large technical facilities worldwide.

He is now changing from General Electric in Stuttgart to Darmstadt. In his role as Technical Managing Director, he is responsible for the construction of the FAIR facility as well as for the operation and further development of the existing accelerator facilities.

Jörg Blaurock studied mechanical engineering at the Helmut Schmidt University in Hamburg. Following a variety of experiences in industry he joined Alstom, today General Electric, in 2007 where he worked in a number of positions. Most recently he was Managing Director and responsible for the delivery of utility steam generators for electricitygenerating fossil-fuel power stations.

Page 2 of 7 New Study confirms Antihydrogen Charge is Neutral A recent experimental result published in Nature by the ALPHA collaboration, improves upon the direct measurement of antihydrogen charge neutrality. This is a precision test conducted in pursuit of answers to the question of why the universe today is predominantly made of matter. According to the Standard Model, that predicts a universe composed of half matter and half antimatter, antihydrogen atoms should be charge neutral.

The silicon tracker detector (courtesy: University of Liverpool).

However, experiments currently underway at the Antimatter Decelerator at CERN are all looking for physics beyond the Standard Model to address this question of baryon asymmetry by comparing measured properties of antimatter against the known equivalent quantities in matter systems.

Charge neutrality is not expected to be broken in antihydrogen, and as such all current antimatter experiments assume it to be true. This measurement constitutes an empirical verification of this assumption, as well as a fundamental symmetry measurement in its own right. Even a tiny putative charge in the antihydrogen system would have significant implications for physics in general, and prosaically create systematic effects in other measurements such as those of antimatter

gravitation currently in progress or proposed to take place at CERN. The result presented in the paper represents a twenty-fold improvement on the bound of the antihydrogen charge achieved by using a new technique involving stochastic acceleration. In this technique, antihydrogen is first formed, trapped, and held in an atomic magnetic-minimum trap. By subjecting the trapped anti-atoms randomly to pulsed electric fields, any charged particles will eventually be accelerated out of the trapping potential. Using a comparison of trap survival with and without the acceleration fields, and comparing the expectation to simulations, the ALPHA collaboration set a new limit on antihydrogen charge as < 0.71 parts per billion (of an electron charge) at a 90% confidence level. Interestingly, this bound on antihydrogen indirectly improves the measurement of the positron charge under the assumption of charge neutrality and using the best measurements of the antiproton charge.

ALPHA is an international collaboration with over 50 researchers in 13 institutions world-wide. This study is the first precision result from the ALPHA-2 apparatus, a device focused on making precision measurements with trapped antihydrogen atoms.

Photograph of the inside of the ALPHA experiment (courtesy: ALPHA).

Further information: M. Ahmadi, et al., â&#x20AC;&#x153;An improved limit on the charge of antihydrogen from stochastic accelerationâ&#x20AC;?. Nature. 529, 373â&#x20AC;&#x201C;376 (2016). doi:10.1038/nature16491.

Page 3 of 7 News in Short First anions trapped in Penning trap The trapping of anions in a Penning trap and their pre-cooling with electrons is an important milestone towards the demonstration of laser cooling of La-. The group of PD Dr. Alban Kellerbauer, based at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany has just achieved the trapping of gold anions in their Penning trap for the first time.

The image on the right shows the ions captured in the trap, then ejected downstream onto a microchannel plate detector with a phosphor screen. The cross indicates the center of the screen, the circle (radius in mm) provides a scale. More news will follow soon â&#x20AC;&#x201C; watch this space !

MCP image of Au anions captured in a Penning trap.

New Collaboration Member We are delighted to welcome Dr. Marcoen Cabbolet from the Department of Philosophy at the Free University of Brussels (VUB).

Dr. Cabboletâ&#x20AC;&#x2122;s work focuses on the theory of possible fundamental principles underlying repulsive gravity and hence a good match to our research ambitions.

Welcome !

Page 4 of 7 2016 â&#x20AC;&#x201C; a LEAP Year Since 1990 the LEAP (Low Energy Antiproton Physics) conference is held every two or three years to discuss the latest findings and exchange information about research with low energy antiprotons.

There has been some remarkable progress recently in experiments with low energy antiproton

Experts from around the world discussed the latest findings in antiproton physics and related fields.

They discussed future experiments and how to take maximum benefit from the improved beam quality that new facilities will provide.

The scientific program consisted of invited and contributed talks which allowed research leaders to present their latest findings. Poster sessions in the evenings of the first two days allowed for further discussion.

Following a welcome reception on the Sunday evening, LEAP started with a session on challenges

physics and new facilities such as the Extra Low Energy Antiproton Ring (ELENA) or the Facility for Low energy Antiproton and Ion Research (FLAIR) will offer even more exciting prospects for hitherto impossible experiments.

Between 6th â&#x20AC;&#x201C; 11th March 2016 the antimatter research community met in the beautiful town of Kanazawa, Japan.

related to exotic particles, including talks about dark pions as dark matter, matter-antimatter asymmetry, and cosmic antiparticles.

After lunch participants learned about a range of recent research results in antihydrogen charge measurements, antihydrogen beam production and Hypernuclei.

The morning of day 2 was dedicated to the challenges related to spectroscopy studies, CPT and gravity studies. The more theoretical nature of this session was contrasted by hands-on news from the construction of the ELENA facility and advanced beam diagnostics developments.

Page 5 of 7 Wednesday morning gave conference delegates an opportunity to find out about the latest results in precision atomic and nuclear masses, together with news from the ATRAP and GBAR collaborations An excursion to Shirakawa-go which was declared a World Heritage Site by UNESCO in 1995 completed this day. Despite the rain the excursion was a welcome break from the talks in the middle of the week and allowed participants to have discussions in a historic environment.

A full day of talks followed on Thursday. It started with charm hadron physics and measurements done by the ASACUSA collaboration and later in the day included for example a discussion of recent results in antiproton-nuclear annihilation cross sections at low energies, as well as an update on the status of the low energy facilities at FAIR. Progress was presented in the commissioning of the CRYRING and HITRAP facilities and possible routes towards an FLAIR facility at FAIR were indicated.

Following a banquet in Tujike-Teien on Thursday evening the final day included talks about the results from studies into the relative biological efficiency of antiprotons and latest information about measurements using muon beams.

Conference chairman Prof. Yasunori Yamazaki from RIKEN in Japan concluded: â&#x20AC;&#x153;From the feedback we received we know that the participants

enjoyed the stimulating environment this LEAP has provided. Kanazawa provided us with an exceptional surrounding to discuss the latest findings in our field. We are now looking forward to the next edition of LEAP which will take the community to Paris, France in 2018.â&#x20AC;?

Page 6 of 7 Best poster awards During LEAP2016 two prizes were awarded to young researchers who presented posters of exceptional quality.

These prizes were sponsored by Nature Physics and consisted of a certificate, a cash amount, and a 1 year subscription of Nature Physics.

Takashi Higuchi, who is a member of the BASE collaboration displayed a summary of results from the 2015 antiproton run.

Bernadette Kolbinger from the Stefan Mayer Institute in Vienna, Austria, presented a poster about 'A Detector for Measuring the Ground State Hyperfine Splitting of Antihydrogenâ&#x20AC;&#x2122;.

Position Vacancies Claude Leon Foundation postdoctoral fellowships Vacancies at Justus Liebig University Giessen, Germany Job opportunities at University of Surrey, UK Postdoctoral fellowship at CANREB, TRIUMF, Canada Vacancies within the OMA project Postdoc in Beam Diagnostics, University of Liverpool / Cockcroft Institute, UK

Please keep us informed about vacancies at your institution.

Page 7 of 7 Selected Events 7th International Particle Accelerator Conference (IPAC16) 8th - 13th May 2016, Busan, Korea EuroNNAc and EuPRAXIA Workshop on a European Plasma Accelerator 29th June - 1st July 2016, Pisa, Italy IsoSiM / HGS-HIRe Summer School 2016 25th - 30th July 2016, Schmitten, Germany International Beam Instrumentation Conference (IBIC16) 11th - 15th September 2016, Barcelona, Spain LA3NET Laser Ion Source Workshop 24th - 25th Oct 2016, Paris, France LA3NET Novel Accelerators Workshop 24th - 26th Oct 2016, Paris, France

The collaboration is often requested to present research highlights and suggest good speakers to various program committees. If you think you or your work should be highlighted, please do not hesitate to get in touch with us.

Please email us your stories, news articles, events and position vacancies to share them with the antimatter community!

www.flairatfair.eu Spokesperson Prof. Dr. Carsten P. Welsch University of Liverpool/Cockcroft Institute, UK carsten.welsch@cockcroft.ac.uk

Co-Spokesperson Prof. Dr. Thomas Stรถhlker, GSI, Darmstadt, Germany t.stoehlker@gsi.de Prof. Dr. Jochen Walz, JG University Mainz, Germany jochen.walz@uni-mainz.de