Cosmic Ray News Bulletin


Author: Frank C. Jones
Laboratory for High Energy Astrophysics, Code 665
NASA/Goddard Space Flight Center
Greenbelt, Maryland 20771, USA
Tel: 1-301-286-5506
Fax: 1-301-286-1682
(Back Issues are available)


Durban ICRC Logo 25th International Cosmic Ray Conference, Durban, South Africa

The second circular for the Durban Conference has now been distributed and since the abstract deadline has now passed the program is now settling into its final form. Although it was possible to submit abstracts electronically camera ready copy will be required for the final copy of the papers. The conference has a home page with links to a registration form (put your name on the mailing list), background material and a discussion of their logo shown here. The site may be reached by setting your browser to the URL

The following report has been received from the conference organizers:

NOTE: Several of the items mentioned in this report can be found in greater detail on the above mentioned web site. This web page should be considerably faster from 12 March, because it is now rerouted through a service provider in Johannesburg.


A total of 960 abstracts were received. Several authors submitted more than the allowed three and these are being referred back to the authors. Our policy is to apply the rule of three per presenting author strictly, otherwise those authors who stuck to the rule will be disadvantaged. We expect that about 900 abstracts will eventually remain.

We have no reliable means of calculating how many of these abstracts will materialise into actual papers. Since the Adelaide conference in 1990, the average number of papers per presenting author was 1.42. Therefore, the maximum scenario for the conference looks like 900 papers/1.42 papers per delegate = 634 delegates. A more realistic scenario is, however, to expect about 450 delegates x 1.42 papers per delegate = 640 papers. This scenario implies that about two-thirds of the abstracts will turn into papers.

We can handle a maximum of 900 papers in the Wednesday to Wednesday programme as posted in the Second Circular, using a 50/50 division between orals and posters, and allowing 10 minutes per oral contribution. If we get only 640 papers, the programme will obviously be easier to schedule.

The division among the three sections is OG 42%, SH 35%, and HE 23%. These are useful numbers to plan the programme in further detail.


The following speaker list was confirmed by the middle of January:

Hess Lecture:

Prof. J.A. Simpson, University of Chicago.

Invited speakers, one per day on 31 July and 1, 2, and 4 August:

V.E. Berezinsky, Gran Sasso Laboratories, Italy, Progress in Theoretical Astrophysics
C.J. Cesarsky, CEA Saclay, France, ISO Mission
L.A. Fisk, University of Michigan, Ulysses Mission
M.C.E. Huber, ESA/ESTEC, The Netherlands, SOHO Mission

Rapporteur speakers (all on Wednesday 6 August):

J. Paul, CEA, Saclay, France, OG 1, 2, 3, 10.1, 10.2, 10.5, 10.6
C.L. Bhat, Bombay, India, OG 4, 10.3, 10.5, 10.6
T.T. von Rosenvinge, GSFC Maryland, USA , OG 5, 7, 10.5, 10.6
A.A. Watson, University of Leeds, England, OG 6, 10.4, 10.5, 10.6
E.G. Berezhko, Yakutsk, Russia, OG 8, 9, 10.5, 11
D. Ruffolo, Chulalongkorn University of Thailand, SH 1
H.V. Cane, University of Tasmania, Australia, SH 2 & 3
J.R. Jokipii, University of Arizona, USA, SH4 &5
K. Kudela, Koscise Observatory, Slovakia, SH 6
J. Knapp, University of Karlsruhe, Germany, HE 1, 2, 6
Y. Suzuki, University of Tokyo, Japan, HE 3, 4, 5

Highlight Sessions:

The programme allows for four Highlight Sessions of one hour each. The topics of these sessions are to be determined by the Programme Committee and their advisors, based on the information in the abstracts as received.

Workshop Programme:

Apart from the TeV Gamma Ray Workshop in the Kruger National Park from 8 to 11 August, which is actually a separate mini-conference, six viable requests for pre- and post-conference workshops have been received. Although the Organizing Committee is not responsible for the scientific organization and content of these workshops, we have made several enquiries to determine their viability.

The topics are not listed here because they are fully described on the Conference Web page. It seems quite possible to schedule all of them in the pre-conference slot on Monday and Tuesday 28 and 29 July (and possibly Wednesday morning 30 July, before the Opening Ceremony). We hope, therefore, to eliminate post-conference workshops and to wrap up the entire Conference on Wednesday evening 6 August, immediately after the Rapporteur session and Closing Ceremony.


The Potchefstroom University printers will produce the volumes. The cost can be kept lower because it is subsidized by the university's infrastructure. The Commission decided in 1991 that the Invited, Rapporteur and Highlight Volume must be produced by a reputable publisher to ensure a wide distribution to libraries. We have chosen World Publishers in Singapore because (a) the Calgary Conference used them, and (b) their price is attractive in comparison to that of other publishers. It is intended that the delivery time of these volumes will be kept to five months from the date of receipt of camera ready copy (three months for printing and two for surface mail)!

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Other Conferences

Following is a list of upcoming conferences that may be of interest to Cosmic-Ray researchers. This list was exerpted from a more comprehensive list of astronomy/astrophysics meetings maintained by the CANADIAN ASTRONOMY DATA CENTRE of the National Research Council of Canada.


Sixth Conference on the Intersections of Particle & Nuclear Physics
START DATE 27 May 97
END DATE 02 Jun 97
CONTACT Susan Ramsay
ADDRESS Los Alamos National Laboratory, MS H844, Los Alamos, NM. 87544
PHONE 505-665-1819

High Energy Cosmic Neutrinos: Origin, Production and Detection
START DATE 02 Jun 97
END DATE 03 Jun 97
LOCATION Marseille - Luminy , France
ADDRESS CPPM, 163 Avenue de Luminy, Case 907, Marseille Cedex 09 France,13288
PHONE 33 (0)4 91 82 72 00
FAX 33 (0)4 91 82 72 99

ITP Conference on Supernova Explosions: their causes and consequences
START DATE 05 Aug 97
END DATE 09 Aug 97
LOCATION Santa Barbara, CA
CONTACT Prof. James B. Harlte
ADDRESS Institute for Theoretical Physics, University of California, Santa Barbara, CA, 93106-4030
PHONE +805 893 2280
FAX +805 893 2431

Galactic Halos: A UC Santa Cruz Workshop
START DATE 11 Aug 97
END DATE 15 Aug 97
CONTACT Dennis Zaritsky
PHONE +408 459 5170
FAX +408 426 3115

Mexican School on Nuclear Astrophysics
START DATE 13 Aug 97
END DATE 20 Aug 97
LOCATION Hotel Castillo Santa Cecilia, Guanajuato,GTO,Mexico
CONTACT Jorge G. Hirsch
ADDRESS Dept of Physics, CINESTAV,Apdo postal 14-740,Mexico,D.F. 07000
PHONE 51-5-747 70 97
FAX 51-5-747 70 96

Aspen Workshop on Gamma Ray Bursters
START DATE 18 Aug 97
END DATE 05 Sep 97
CONTACT Aspen Center for Physics ADDRESS
700 W. Gillespie, Aspen, CO, 81611 PHONE

Fourth Huntsville Symposium on Gamma-Ray Bursts
START DATE 15 Sep 97
END DATE 19 Sep 97
LOCATION Huntsville, AL


TeV Gamma-Ray Astrophysics

Eds. Heinrich J. Voelk and Felix A. Aharonian (Kluwer Acadamic, Dordrecht; reprinted from Space Science Reviews, Vol. 75, Nos. 1-2, 1996)

The study of TeV gamma-ray emission from astrophysical sources has been transformed in the last decade from being an offshoot of cosmic ray physics to occupying a central role in the understanding of various objects that form the focus of high energy astrophysics. This transition became possible when the atmospheric Cherenkov imaging technique gained the capability of distinguishing between hadron-initiated showers and those of photon origin. This collection of papers, the proceedings of the Heidelberg Workshop of October, 1995, provides an excellent overview of the status quo of the field, ranging from reviews of the essentials of experimental techniques, results from extant instrumentation, designs and objectives for imminent and future experiments, and the interpretation of observations and associated theoretical modeling in various contexts.

The proceedings appropriately begin with a review of the Cherenkov technique by the principal pioneer of the field of TeV gamma-ray astronomy, Trevor Weekes, this year's winner of the Rossi Prize. Weekes provides a nice history of the field, culminating in the first light from the Crab Nebula as seen by the Whipple Observatory in 1989. The capability of air Cherenkov telescopes (ACTs) to discriminate between hadronic (i.e. cosmic ray) and photon-initiated air showers is discussed at length in the paper of Hillas, which provides a summary of experimental essentials that is very useful for the non-specialist. For instrumental experts, the paper of Fegan provides a discussion of ACT instrumentation of a highly technical nature. Issues of stereoscopic versus monocular telescopes and the possibilities for wide-angle Cherenkov experiments are discussed in the presentations of Chadwick et al. and Lorenz. Several papers address upcoming and planned experiments. These include ground-based TeV devices such as MILAGRO, which offers half-sky monitoring and almost continuous operation (Yodh), and space missions such as GLAST (Bloom), which extends the discussion down to sub-GeV energies. Spectroscopic aspects in the MeV energy range are emphasized in the presentation of von Ballmoos. The limited but significant consideration of the sub-TeV domain in the proceedings aptly reflects the intimate relationship and interdependence between various portions of the hard gamma-ray band, and the closely-connected role that ground-based and satellite experimentation plays in high energy astrophysics. While the volume describes many experimental aspects comprehensively, it is noticeably thin on contributions from personnel with associations outside the Whipple and HEGRA collaborations.

The current status of observations of sources such as pulsar nebulae and blazars, and upper limits to TeV emission from X-ray binaries, are nicely summarized in the papers of Kifune and Lamb. Hurley discusses the potential for TeV detections of gamma-ray bursts, whose projected optimal TeV fluxes fall below current ACT sensitivity thresholds. The most prominent omission from the observational summaries relates to the recent Whipple upper limits to TeV emission from unidentified EGRET sources possessing supernova remnant associations; these results postdate publication of the proceedings.

Just over half the volume is devoted to the interpretative and theoretical side of the TeV astrophysics field. These include both galactic and extragalactic sources of TeV gamma-rays. Harding presents a review of seminal work on the synchrotron self-Compton pulsar wind model for gamma-ray production in the Crab Nebula, and its extension to Vela-X and MSH 15-52, while Arons discusses the influence of the relativistic wind outflow from pulsars on the wisp structure in the Crab Nebula via plasma processes, and briefly reviews pulsed sub-TeV emission models for pulsars. Drury summarizes the principal predictions of his seminal work on gamma-ray radiation from cosmic rays produced in shell-type supernova, work that has now been superseded by Whipple non-detections and very recent models with several refinements. The proceedings has a large extragalactic component, focusing mostly on the blazar class of active galaxies, but including diverse topics such as emission from clusters of galaxies and topological defects, and the relationship between gamma-rays and cosmic rays. The emphasis on blazars largely underlines the impact that the discovery of TeV gamma-rays from Mrk 421 has had on high energy astrophysics. Three papers on gamma-ray generation are put forth, encompassing both electromagnetic production channels (Schlickeiser), and hadronic modes of emission (Mannheim, Mastichiadis) that couple to extragalactic cosmic ray production studies. While both can explain the TeV observations, discrimination between these two approaches is not afforded by current MeV-TeV spectra. For the hadronic models, associated neutrino emission and prospects for its detection are addressed by Stecker and Salamon. In addition, comprehensive discussions of external absorption of intrinsic blazar TeV photons in collisions with cosmic background fields are presented by the two principal groups in this topical area of research, namely Stecker and De Jager, and MacMinn and Primack. The excitement in this topic highlights the potential of TeV astronomy to go beyond individual sources and probe the early universe.

In summary, the blend of breadth of the discussion and depth of individual focuses makes this book a valuable contribution to the gamma-ray astrophysics literature, and suitable to both the newcomer to the field and the experienced specialist.

Matthew Baring , NASA/Goddard Space Flight Center

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Peter H. Fowler FRS (1923 - 1996)

The sudden death of Peter Fowler, on 8th November last year, has deprived the UK of one of the outstanding physicists of his generation In an age of increasing specialisation he was one of the few scientists capable of making important contributions over a range of topics in physics and astronomy.

Fowler's research career started whilst he was still an undergraduate working in vacations with Cecil Powell's group who were developing photographic emulsion technique as a method of recording tracks of elementary particles. Fowler was to become a leading member of this group. The emulsion technique was used to establish the existence of the p-meson, using plates which had been exposed to cosmic ray particles at mountain altitudes, work for which Powell was awarded the Nobel Prize for Physics in 1950

Fowler's research on the primary cosmic radiation started in the early 1950's with measurements of the abundances of lithium, beryllium and boron in the cosmic rays and the implications of these abundances for the storage time of cosmic rays in the Galaxy. These experiments required exposures at very high altitudes and, because the use of balloons was still a classified activity in the USA, the Bristol group developed their own methods of fabricating and launching large polythene balloons. At the same time Fowler continued to work in particle physics using the cosmic radiation as a source of high energy particles. The advent in the 1960's, of proton synchrotrons producing intense beams of particles with energies up to several tens of GeV meant that. to compete, the cosmic ray studies would have to move to even higher energies. Working with Don Perkins and Klaus Pinkau and using emulsion exposed on aircraft, Fowler made pioneering studies of the physics of particle: energies up to 105 GeV.

In the late 1960's Fowler's interest turned to the question of the abundances in the cosmic rays of elements heavier than iron. Using large rafts. first of emulsion and later of the plastic detector Lexan, he showed that these elements were detectable despite their very low fluxes. He recognized however, that the track detectors could not provide the necessary charge resolution. and he turned to the use of gas scintillation and Cerenkov detectors. With the. ingenuity which was the hallmark of all his experimental work he developed a novel design of detector with spherical geometry. A series of these detectors was built and flown, first on balloons, and later on the satellite Ariel 6. These experiments showed that, at the highest charges the cosmic ray abundances were significantly different from those expected from propagating material with solar system abundances through the Galaxy.

After his official retirement in 1988 Fowler's energy and enthusiasm moved away from cosmic ray physics to methods of measuring very high temperatures using the thermal broadening of neutron capture resonances He showed how this technique could be used to measure the temperatures of moving turbine blades in aircraft test-beds, and at the time of his death, was investigating the possibility of using it to calibrate thermocouples for geophysical measurements deep below the surface of the: Earth.

Elected a fellow of the Royal Society in 1964, a fellow of the Institute of Physics in 1968 and awarded the Royal Society's Hughes medal in 1974, Fowler was notoriously indifferent both to honours and to academic politics and administration. An inspiring and demanding supervisor of research students, he was at his best in individual interaction. when both his phenomenal powers of mental arithmetic and his ability to got to the heart of the problem on the back; of an envelope within a few, minutes were astonishing. His knowledge of physics was prodigious and he was an invaluable source of advice to both colleagues and students.

Fowler was the grandson of Lord Rutherford and the son of Sir Ralph Fowler. He married Rosemary Brown in 1949, and they had three daughters.

Rodney Hillier

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