Astronomy & Astrophysics in India : Emerging challenges in Data - - PowerPoint PPT Presentation

Astronomy & Astrophysics in India : Emerging challenges in Data Flow

Tarun Souradeep, IUCAA, Pune

NKN 2nd Annual Workshop

• IISc. , Bangalore

17th Oct 2013

Dynamic range of phenomena

10-35sec

Rapid Ad

Advanc nce e in Obser erva vatio tiona nal l capab abil ility ity  Da Data a drive ven scienc ence

Model eling ing phen enomena with high gher er dyna namic rang nge e increasing easingly y possibl sible e with growth th in computation

• n

(Den ensity sity (gm/cc) c): : cosm smic =10-29

29,Ear

Earth=10, h=10, Neutron utron star ar=1 =1012)

2)

Billion light years(lys) Million lys Thousand lys Light days

Knowledge & Data flow in A&A

Theoretical Modeling Numerical simulation

Large dynamic range, Diverse physics

Observations: Data acquisition

Large volume, high sampling rates, rapid response

Data Distribution

Multiple analysis centers, Public , large distributed, global science collaborations

Data Analysis

Huge data, v multi-parameter Follow up

Numerical Simulations in Astrophysics

Examples of simulations :

• Large scale structure of the Universe
• Formation & interaction of galaxies
• Formation of stars and solar systems
• Complex structure of the Sun

Common features :

• Involve upto 109 or more “particles”
• Complex interactions between particles:

gravity, magneto-hydrodynamics etc

• Long time-scale evolution, many steps

Large scale Universe : Complex web of cold dark matter Collision of 2 gas clouds leading to formation of stars Galaxy formation & evolution

• Gravitational contraction/collapse/stellar dynamics
• Gas Dynamics - often supersonic, relativistic
• MHD, Poynting Flows
• Radiative Transfer
• Stellar structure and evolution
• Particle acceleration
• Merger of neutron stars/black holes

N-body simulation, Smoothed Particle Hydrodynamics SPH, CFD CFD+Maxwell PDE solvers, Green’s Function, Monte Carlo PIC, Monte Carlo

Astrophysics via large numerical simulation

Numerical Relativity PDE, Nuclear Chemistry, Thermodynamics

Ongoing HPC-based Astronomy Research

• IUCAA, Pune: MHD, Dynamos, N-body simulation, Structure formation,

Radiative transfer, Molecular chemistry, Dust scattering, CMB analysis, Gravitational Waves, Pulsar search, Automated classification....

(IUCAA is linked to A&A research community in the University of India)

• TIFR, Mumbai: Stellar structure, Helioseismology, Gravitational lensing
• IIA, Bangalore: Radiative transfer, MHD, N-body simulation, Star Formation
• IISc, Bangalore: Plasma astrophysics, Galaxy dynamics, Hydrodynamics
• HRI, Allahabad: Cosmological simulations, Accretion hydrodynamics
• IISER, Mohali: N-body simulation, Structure formation
• Delhi University: Solar MHD, Gravitational Waves
• SNBNCBS, Kolkata: Accretion flows, Molecular chemistry
• NCRA, Pune: Real-time radio interferometry, Pulsar search & timing
• +++

Plenitude of Observations

Planck CMB sky map

Planck: 12 million pixels of temperature/polarization (COBE detection: 4000 pixels) Measurements of the Cosmic Microwave Background

30 GHz 44 GHz 70 GHz 100 GHz 143 GHz 217 GHz 353 GHz 545 GHz 857 GHz

CMB Maps at Planck Frequencies

Planck Early Release 2011

Credit: ESA, HFI & LFI consortia

SZ clusters from Planck

Large Observational data sets

8000 deg2 287 million objects 1.3 million spectra 10 TB imaging data 2 TB catalogue data

Sloan Digital Sky Survey

13

470,992,970 point sources, 1,647,599 extended source

Large surveys

6283 catalogues

14

Time Domain Astronomy

• Real-time search in and characterization of 4-D data arrays
• position (x,y), colour (wavelength), time
• Large surveys are in the offing at many places across the world

including India. Indian interest will include the processing of data from local as well as some of the international facilities

• Most of the computation will be for automatic detection,

characterization and classification of transient events, on which the decision of follow-up operations will be based

• Need both large network bandwidth and high compute power

Catalina Real-Time Transients Survey

CSS090429:135125-075714

Flare star

CSS090429:101546+033311

Dwarf Nova

CSS090426:074240+544425

Blazar 2EG J0744+5438

Vastly different physical phenomena, and yet they look the same

!Which ones are the most interesting and worthy of follow-up?

CRITICAL: Rapid, automated transient classification & distribution

International Virtual Observatory Alliance

Imminent transient Data deluge

• Forthcoming on a time scale ~ 1 - 5 years: ~ 1 TB /

night, ~104 transients / night (PanSTARRS, Skymapper, VISTA, VST…)

• Forthcoming in ~ 8 - 10 years: LSST, ~ 30 TB /

night, ~ 105 - 106 transients / night

• Observational follow-up needs:
• Rapid photometric/positional monitoring
• Rapid spectroscopy
• Information/computation infrastructure

A major, qualitative change!

• Now: data streams of ~ 0.1 TB / night, ~ 10 - 102 transients /

night (CRTS, PQ, PTF, various SN surveys, asteroid surveys)



Transient classification technologies are essential

Mega-Science ventures in Indian A&A

(upcoming & advanced proposals)

20

ASTROSAT

FIVE astronomy payloads for simultaneous multi-band observations:

• 1. 2x 40-cm Ultraviolet Imaging

Telescopes (UVIT)

• 1. 3 Large Area Xenon
• 2. Proportional Counters (LAXPC)
• 3. A Soft X-ray Telescope (SXT)
• 4. A Cadmium-Zinc-Telluride
• 5. coded-mask imager (CZTI)
• 6. A Scanning Sky Monitor (SSM)
• 7. consisting of three one-dimensional
• 8. position-sensitive proportional
• 9. counters with coded masks.

Thirty Meter Telescope

Caltech University of California Canada Japan China India (TMT-India proposal) 30m equivalent primary mirror,

492 segments, 1.4m each, FOV 20 arcmin, 0.31 to 28 micron, Angular resolution with AO ~7 mas

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Square-kilometer array (SKA)

Proposed/Ongoing Indian participation

• Next big step in Radio Astronomy (an international telescope)
• Total collecting area of 1 million sq. meters (about 30 times the GMRT) !
• Will be spread over a much larger area : ~ thousand km !! (contintental size)

LIGO-India proposal

GW observatory on Indian soil

4km arm length Laser interferometer

A Century long Wait

• Einstein’s Gravitation (1916- ):
• Beauty : symmetry in fundamental physics –mother of gauge theories
• & precision : matches all experimental tests till date to high precision

Gravitational Waves -- travelling space-time ripples

are a fundamental prediction

• Existence of GW inferred beyond doubt (Nobel Prize 1993)
• Feeble effect of GW on a Detector  strong sources

GW Hertz experiment ruled out. Only astrophysical systems involving huge masses and accelerating very strongly are potential detectable sources of GW signals. GW  Astronomy link Astrophysical systems are sources of copious GW emission:

• GW emission efficiency (10% of mass for BH mergers) >>

EM radiation via Nuclear fusion (0.05% of mass) Energy/mass emitted in GW from binary >> EM radiation in the lifetime

• Universe is buzzing with GW signals from cores of astrophysical

events Bursts (SN, GRB), mergers, accretion, stellar cannibalism ,…

• Extremely Weak interaction, hence, has been difficult to detect directly

But also implies GW carry unscreened & uncontaminated signals

96% universe does not emit Electromagnetic signal!

Global Network of Adv. GW Observatories

LIGO-LLO: 4km LIGO-LHO: 2km+ 4km GEO: 0.6km VIRGO: 3km KAGRA 3 km (2017)

Network  1. Detection confidence 2. Duty cycle 3. Source direction 4. Polarization info.

LIGO-India

Time delays in milliseconds India provides almost largest possible baselines.

(Antipodal baseline 42ms)

LIGO-India: … the opportunity

Science Gain from Strategic Geographical Relocation

Source localization error

Courtesy:

• S. Fairhurst

Launch of Gravitational wave Astronomy

Highly Multi- disciplinary

Astro++

Data from Gravitational wave experiments

• Data comprised of
• Gravitational wave channel

(ASQ)

• Environmental monitors
• Internal engineering monitors
• Multiple data products

beyond raw data

• Reduced data sets
• Level 1: gravitational wave

and environmental channels

• Level 3: only gravitational

wave data.

• Different sampling rates

IFO Env CH Health

1TB of raw data per day!

GW Data volume

Time series data sampled at 16Hz - 16kHz

Thousands of monitoring channels “science channels”: ~1% of total data per detector: 2B x 16kHz = 32kBps = ~1TB/year

Advanced LIGO data volume: ~1petabyte / year

Conflicting Requirements:

• Low ‘seismicity’ (ground noise PSD)
• Low human generated noise, …..
• Air connectivity, road connectivity, data connectivity,…
• Proximity to Academic institutions, labs, industry preferred, …

LIGO-India Site search

High data connectivity required from a LIGO-India site at relatively remote, underdeveloped region in India.

 Role of GW data centre

 Tier-2 data & compute centre for archival of GW data and analysis  Bring together GW scientists & data-analysts within the Indian science

community.  Puts India on the global map for international LIGO Science Collab. wide facility.  Large University sector participation via IUCAA

• Tier2 like GWDA centre: ~200 Tf peak capability [~ 2014]

Network: gigabit+ backbone, NKN, Few Gigabit dedicated link to LIGO Caltech

• Currently prototype data centre:

IUCAA data centre: (Jan 2013) 30 Tf , 600 Tb [94 nodes : 2 x 8-core Intel

Xeon Sandybridge, 128 GB RAM/node, Infiniband interconnect]

• 10Tf for GW: Required set up tried out, 0.5-0.8 Gbps data transfer

All infrastructure (for expansion to ~300 Tf ) in place before leaving IUCAA.

[total investment ~ 2 M USD]

• GW Data Centre @ IUCAA

Multi-messenger astronomy

Joint analysis with other observatories

for confident detection studying physics of the emitting system testing general relativity (speed of GW)

Quickly send triggers to other facilities Publish triggers in databases (VOEvents format) Demonstrated with a number of facilities

How does one transport increasingly large astronomical data ?

Thank you !!!

Modelling Star Formation using SPH

35 million SPH particles. 6 million core-hours

LIGO-India mega-science project: Salient points

• On Indian Soil with International Cooperation (no competition)
• Involvement at the threshold of a major science discovery!!!
• AdvLIGO-USA precedes LIGO-India by ~3 years. Staggered time-line  dual advantage.
• Indian experimenters would participate in Adv-LIGO-USA
• Significant US expertise will pave way for faster execution of LIGO-India
• US hardware contribution ready : no uncertainty in timeline
• Adv.LIGO is the Largest NSF funded project in USA
• LIGO-India by NSF positive reviews , NSB approval for NSF to proceed as it deems best.
• Expenditure entirely in Indian labs & Industry.
• Very significant Industrial capability upgrade. Indian DAE labs &

Industry assessed to be in position to carry out phase-I of LIGO-India.

(Senior LIGO team visited Indian labs & facilities in Aug ,Oct, Dec 2011, Feb 2012]

• Well defined training plan  Generate large number (~100) of highly

trained HRD in areas of wide application in S &T.

• Major data analysis centre for the entire LIGO network. Huge
• pportunity for Indian University participation.

Nat ationa ional l Kn Knowledge

• wledge Net

etwork work

• GW data centre will need a high

bandwidth backbone connection for data replication from Tier-1 centres at LIGO sites in US, India, GW detectors in Europe Japan,

• As well as for users to use the

facility from their parent institutions.

• NKN can potentially provide this

facility between IndIGO member institutions.

• International connections, EU-

India Grid