ISSI meetings on "the disk-magnetosphere interaction around transitional millisecond pulsars"

Neutron stars in low-mass X-ray binaries are assumed to be spun up to millisecond rotational periods by accreting matter transferred by a companion star. When the rate of mass transfer decreases at the end of this Gyr-long X-ray bright phase, a radio pulsar turns on, powered by loss of rotational energy of the neutron star. In 2013-2014, the evolutionary link between these two classes of objects was finally proven by the discovery of transitional millisecond pulsars, sources alternating between accretion- and rotation-powered states depending on the rate of mass in-flow towards the neutron star. The observed transitions take place on time scales as short as a couple of weeks, involving also an intermediate state possibly explained by centrifugal inhibition of accretion. These sources are unique laboratories to study the interaction between a quickly rotating magnetosphere and the in-falling plasma, the evolutionary paths of millisecond pulsars, and the formation and structure of accretion disks. It is now timely to bring together a number of radio, X-ray and gamma-ray observers, as well as theoretical astrophysicists, to interpret the observational wealth yielded by a multi-wavelength approach, with a view to unveil the fundamental processes probed by these unique systems.

Participants 1st meeting

A. Papitto (IEEC-UAB, Spain; Leading scientist)
A. Archibald (ASTRON, Thew Netherlands)
C. Bassa (ASTRON, The Netherlands)
E. Bozzo (Univ. of Geneva, Switzelrand)
L. Burderi (Univ. of Cagliari, Italy)
F. Coti-Zelati (INAF-OA Brera; Italy)
C. D'Angelo (Univ. of Amsterdam, The Netherlands)
T. Di Salvo (Univ. of Palermo, Italy)
C. Heinke (Univ. of Alberta, Canada)
J. Hessels (Univ. of Amsterdam, The Netherlands)
M. Falanga (ISSI Bern, Switzerland)
C. Ferrigno (Univ. of Geneva, Switzelrand)
M. Romanova (Cornell Univ., United States)
H. Spruit (MPA-Garching, Germany)
T. Tauris (Univ. of Bonn, Germany)
D. Torres (IEEC-UAB, Spain)


Participants 2nd meeting

E. Bozzo (ISDC, Switzerland)
N. Degenaar (Cambridge/API, UK)
L. Burderi (Univ. Cagliari, Italy)
V. De Falco (ISSI, Switzerland)
T. Di Salvo (Univ. Palermo, Italy)
R. Lovelace (Cornell, USA)
M. Falanga (ISSI, Switzerland)
C. Ferrigno (ISDC, Switzerland)
A. Papitto (OAR, switzerland)
A. Patruno (Leiden, Netherlands)
M. Romanova (Cornell, USA)
A. Sanna (Univ. Cagliari, Italy)
D. Torres (ICE Barcelona, Spain)