Welcome to the Osservatorio Astronomico di Roma and the Astro-GR/VESF School

Pau Amaro Seoane, Raffaella Schneider, Luigi Stella

A brief summary of studies at OAR related to GWs

-  Magnetars -  Double White Dwarf Binaries - Short Gamma Ray Bursts -  Stochastics GW background -  E.M. Follow up programs -  eLISA sources and Athena

The B-field of Magnetars Very strong internal B-fields in a newborn differentially rotating fast-spinning neutron star For initial spin periods of Pi∼1–2 ms, differential rotation can store ∼1052(Pi/1 ms)2 ergs, that can be converted into a magnetic field of up to 3x1017 (Pi/1ms)-1 G. (efficient dynamo might be limited to ~3x1016 G) (Duncan & Thompson 1992)

Bd Bt

Bd ~ 1014-15 G outer dipole field (spin-down, pulsations) inferred from spin-down rate (and confirmed through the energetics and fast variability properties of the “ringing tail” of Giant Flares from SGRs) Bt > 1015 G inner toroidal field (energy reservoir): lower limit from: L(persistent) x age ~ 1047 ergs

Fast spin (few ms) and differential rotation generate

internal toroidal field B > 1015 G

Magnetars: Bursts

-  energy release ~1038-1041 ergs -  subsecond duration - often emitted in bunches

SGR 1806-20: Giant Flare of 2004 Dec 27

(Mereghetti et al. 2005)

(Palmer et al. 2005 Hurley et al. 2005)

Moon reverberation seen !

First detection of Quasi Periodic Oscillation in a Magnetar

Total power spectrum of XTE high resolution data

XTE was observing a cluster of galaxies, a constant and low “background” level for the SGR1806-20 hyperflare

Newborn Magnetars as Gravitaional Wave Sources

(for Virgo Cluster distance, 20 Mpc) -  GW signal at ~1 kHz evolving in 1 week - Consider initial spin period of 2ms Most promising region is Bt > 1016.5 G and Bd < 1014 G -  Required no. of templates is very large Expected magnetar birth rate in the ~2000 galaxies of Virgo: ~ 1 yr-1 ! Potentially Very Interesting GW Event Rate in Advanced LIGO/Virgo-class instruments

2x1016 G 6x1016 G

~ 1 week, ~ 108cycles

Nov 2002 Nov 2001

RXJ0806.3+1527: a double degenerate binary system (2WDs) with an orbital period of 5.4min !! One of the best target for gravitational wave calibration with eLISA

Double White Dwarf Binaries (AM CVn-like)

Short Gamma-Ray Bursts

•  GRBs duration distribution is bimodal (e.g. Briggs et al. 2002) –  0.1-1 s -> Short bursts –  10-100 s -> Long bursts

•  Short GRBs are harder than long GRBs

(e.g. Fishman & Meegan, 1995;Tavani 1996).

Swift

BAT Burst Image

T<10 s, θ < 4'

1.  Burst Alert Telescope triggers on GRB, calculates position to < 4 arcmin 2.  Spacecraft autonomously slews to GRB position in 20-70 s 3.  X-ray Telescope determines position to < 5 arcseconds 4.  UV/Optical Telescope images field, transmits finding chart to ground

BAT Error Circle

XRT Image

T<100 s, θ < 5''

T<300 s

UVOT Image

Instrumentation Burst alert telescope (BAT) 10-150 keV X-ray telescope (XRT) 0.3-10 keV

UV-optical telescope (UVOT) U-I

- USA, I, UK mission dedicated to GRB Science

Coalescing binary models

Association of Short GRBs to low SFR galaxies + absence of SN : Merging (or Coalescing) binary models for Short GRBs

Neutron Star + Neutron star (NS-NS) or Neutron Star + Black hole (NS-BH) Strong Gravitational Wave Sources !

2014 Astro-GR/VESF School

- Emphasis on the astrophysical counterparts of gravitational wave (GW) sources and events; required to confirm GW detections

-  Bring together the high frequency (Virgo/LIGO) and low frequency (eLISA) GW communities

-  Advanced Virgo and LIGO operational in a few years: ~100 deg^2 error regions expected by the late 2010’s

-  Astro-GR Meeting and VESF school merged this year: aiming at cross-fertilisation across different communities (GWs, Ap), while also teaching young scientists and students.

Astro-GR Meeting Series

•  The  scope  of  VESF  is    promo1ng  the  physics  of  gravita1onal  waves,and  the  collabora1on  among  groups  in  different  countries  

-­‐>  VESF  goals  and  func1ons  revised;  main  aims:      -­‐  to  foster  the  par1cipa1on  of  a  larger  community,  especially  in  the      field  of  data  analysis  (    -­‐  to  help  coordinate  and  run  mul1messenger  programs  (see  enthusias1c        response  to  the  MoU  call)    

     •  In  2008  VESF  was  composed  of  48  groups,  ~  200  members  from  Virgo,  ~  200  non-­‐

Virgo  members  belonging  to  European  universi1es,  laboratories  and  astronomical    observatories.    

-­‐>  New  census  necessary:  will  begin  in  July  2014  

-­‐  All  groups  to  reply  (or  apply)    -­‐  revision  of  par1cipant  list  and  LoI  -­‐  1  VESF  Council  representa1ve  per  group  with  >  3  people    

   

The  Virgo  EGO  Science  Forum  (VESF)  in  the  Advanced  Detector  Era  

VESF  Schools  (2012  -­‐>  )  

•  2012  –  “VESF  School  on  Advanced  Gravita1onal  Wave  Detectors”  –  Held  at  Virgo  Site  Cascina  –  Jan  18-­‐22.  18  Par1cipants      

•  2013  -­‐  VESF  School  on  ”Gravita1onal  waves,  neutrinos  and  mul1wavelenght  

e.m.  observa1ons:  the  new  fron1er  of  astronomy”,  held  at  INAF-­‐OAR  in  Monteporzio  Catone    (Italy)  -­‐  April  15-­‐18.      

         35  Par1cipants,  18  speakers  

•  2014  –  VESF    School  (run  jointly  with  ASTRO-­‐GR)  “Astrophysics  of  low  and  high  frequency  Gravita1onal  Waves”  

         to  be  held  at  INAF-­‐OAR  in  Monteporzio  Catone    (Rome,  Italy)  –July  14-­‐18.            ~30  Par1cipants,  22  speakers    •  2015  –  two  VESF  Schools  planned  in  collabora1on  with  GRAWITON  ITN  

 *  April/May    –  General  School,  Virgo  Site  Cascina  (Italy)      *  Nov                          -­‐-­‐  Data  Analysis  School,  Birmingham  (UK)    

 •  2016  –  TBD  (in  collabora1on  with  NewCompStar  and  GRAWITON)  

Financial support from -  EGO/VESF -  INAF (Italian National Institute of Astropshyics) -  Albert Einstein Institute

Logistics -  Coffee breaks/lunches: 2^ floor -  Vending Machines: basement -  Wireless: TBD -  Transportation -  Different room tomorrow ?

How does it work: -  we divide in 4 groups, 1 group per day -  each group picks up a person to give a summary talk on Friday

Group 2 - Tuesday Imma Donnarumma Massimo Dotti Andrés Escala Viviana Fafone Alessia Franchini Felipe Garrido Bruno Giacomazzo Giuseppe Greco Leonardo Gualtieri Jafar Khodagholizadeh Diana Lumaca

group 1 - Monday Lorenzo Aiello Tal Alexander Pau Amaro-Seoane Manuel Arca Sedda Stefano Ascenzi Maria Grazia Bernardini Marica Branchesi Igor Bulyzhenkov Jordi Casanellas Claudio Casentini Sabrina D’Antonio Simone Dall’Osso

Groups 3 - Wednesday Michela Mapelli Stefania Marassi Francesca Marchi Andrea Maselli Simone Mastrogiovanni Cristián Maureira Fredes Cristiano Palomba Paolo Pani Andrea Passamonti Silvia Piranomonte Nataliya Porayko Andrea Possenti

Group 4 - Thursday Alessio Rocchi Elena Maria Rossi Sabina Sabatini Raffaella Schneider Bernard Schutz Alberto Sesana Günter Sigl Mario Spera Adamantios Stavridis Luigi Stella Ian Vega Andrea Vicere Brunetto Ziosi