The 4MOST Galactic Surveys - Public spectroscopic surveys Sofia Feltzing Lund Observatory
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The 4MOST Galactic
Surveys
Public spectroscopic surveys
Sofia Feltzing
Lund Observatory
Why study galaxies?
• Understanding the build up of structure in the
Universe requires:
-understanding galaxies
★ which means understanding how the baryons
are distributed and why
★ a typical star is typically in a spiral/disk galaxy
- understanding
★
disk galaxies
which means that we need to understand how
the disks work
- Milky Way is a good hunting ground
SDSS I-III
100°
Perhaps one of the most well-known pictures of Galactic archeology – SDSS field of streams.
In the disk of the Milky Way there is a lot to be understood (probably more than in the halo)
and its a lot harder. Gaia – 4MOST – … – E-ELT
z ≈ 3.4
z=0
z≈1
AgeUniverse ≈ 6Gyr
Elmegreen & Elmegreen (various)
Gaia changes
The Gaia revolutionall
10% accuracy @ 10 kpc
10% accuracy @ 100 pc
RVs down to ~15.2 and abundances to 11
Unparalleled dataset with motions and positions for 10 9 stars across the Milky Way
Gaia on its own is not enough. We need ground-based spectroscopy From A. Helmi @ ESO in 2020
10 4 times more stars with full phase-space information; 106 volume increase; 100x more accurate
to get the 3D motions and the elemental abundances that are
needed for a complete understanding Completely of new view of
the Milky the Galaxy!
Way.
Gaia complements
N
1+2
>106 LR stars
105 + 105 HR stars 107 LR stars
>105 HR stars
2.5 m 4m
4m
S
GALAH! 2
VLT
1-2 107 LR stars 8m 106 HR stars 105 HR stars
1-2 106 HR stars 4m 2.5 m
! 4m 105 HR stars
http://www.ing.iac.es/weave/ http://www.roe.ac.uk/~ciras/MOONS/VLT-MOONS.html
http://www.4most.eu www.mso.anu.edu.au/galah/ https://desi.lbl.gov
http://www.gaia-eso.eu APOGEE - see SDSS web
λ-coverage for the new surveys
R~20 000
Spectral resolution
>5000
>5000
2500
4000
7500
APOGEE, MOONS —>
MOONS: 0.7-0.9, 1.17-1.26, 1.52-1.63 μm
https://www.4most.eu • 4MOST survey facility will go on the VISTA telescope and provide 1-2 million high-res spectra, 10-20 million radial velocities • PDR in June 2016; FDR in Jan 2018; operations start 2021
4MOST
- ~2400 fibres - New Wide-field Corrector, fibre
- Large, overlapping patrol areas positioner and three spectrographs
enables dense target packing
and special high-resolution fibres
- Spectrographs mounted on telescope
fork (gravitation invariant)
- Closest separation ~15 arcsec
- Reconfiguration time
Limiting magnitudes
20 000
10 min
HR
2h, SNR 140/Å
16
5 000
Abundances, 2h
SNR 30/Å
Radial velocities, 2h
20 SNR 10/Å
LR4MOST • Survey facility - Instrument, science operations, data products, science - All hemisphere (South) - Run all-sky 5 year public surveys in parallel - Consortium surveys (65% time for consortium) - ~15 million spectra for community proposals (2018)
4MOST ! Galactic science
How far can we reach?
WEAVE and 4MOST
red giants
WEAVE and 4MOST
best dwarf stars Old/metal-rich
Old/metal-poor
Sun
Young/metal-rich
hz (thin) ~300pc hz (thick) ~1000pc
~8kpc
Local solar neighbourhood
(e.g., Bensby et al. 2014)
nthick/nthin (solar neighbourhood) ~0.1~3 M
~0.2 M
~15 M
~2.5 M
Low resolution High resolution!
•
Low resolution halo
~3M objects
• >10 000 square degrees, contiguous sky coverage
• Survey PIs: Amina Helmi, Mike Irwin
!
– to study the formation and evolution of the Galactic halo
– to deduce the
– 3D distribution of mass in the Galaxy,
– its substructure
– its assembly history
Example: Measurement of the
possible perturbations induced by
clumps on the spatial and
kinematic properties of cold
streams. This may lead to
constraints of the mass spectrum
of perturbers and on the nature of
halo dark matter.!
High resolution halo
• ~0.2M objects
• >10 000 square degrees
• Survey PI: Norbert Christlieb
!
– metal-poor (i.e., [Fe/H] < −1.0) stars
– as chemo-dynamical tracers of the formation and chemical enrichment of the
Galaxy,
– for studying the physics of star formation in metal-poor environments
– for studying the properties of the first generation of stars (e.g., initial mass
function; rotation).
Example questions:
• What is the shape of the low-metallicity tail of the halo MDF, is it continuous ?
• Does there exist a sharp cutoff of the halo MDF?
• Is the MDF constant throughout the halo?duce a group similar to
et al. 2009), it is diffic
spiral arms and bar as
The characteristics o
!
LR disk and bulge instance, determination
Sun–Galactic Centre r
45 ◦
(Hammersley et al
• ~15M objects
• Several sub-surveys existence of one or two
1432 T. Antoja et al.
• Survey PIs: Cristina Chiappini, Ivan Minchev, Else Starkenburg It would be worth exp
! combined spiral-bar al
– To understand the current Milky Way disk structure and dynamics of the
(bar, scope spiral of the pres
arms, radial migration of stars) orientation could produ
– To study the chemo-dynamics of the disk, which, when combined with item one
it will allow us to recover the evolutionary history of the disk not change the conclus
– To understand the formation of the Milky Way bulge using bothwe changeand
chemical the relative
dynamical information or their pattern speeds
dominated by one of th
Example: Milky way bar creates
moving groups in velocity distribution. one pattern exceeds the
Y (kpc)
Gaia + 4MOST —> 10kpc are much closer to the
the parameters of the s
literature seem to indic
V (km/s)
Simulations with other
X have
(kpc) confirmed that the
Figure 10. Zoom of the density response at solar position for the TWA
on the
model (top) and PERLAS model (bottom) parameters
for all particles (all integration prov
Figu
times) in the simulation of Fig. 9.
We could also cons simu
IC1
U (km/s) density in our region of study (near solar positions) is significantly the fi4MOST simulator
• Simulate throughput, fibre assignment, survey
strategy
• Verifies total survey plan and quality
• Consortium provides full forward modelling tools:
-Astronomer provides real or simulated targets
-Create fields and observing schedule including
competition from other surveys
Boller, Dwelly and collaborators at
MPE, Garching#This is the night reports logfile for simulation: "round8/b/run04b"! #This log was first written at: Tue Nov 10 16:51:03 2015! #Original filename: night_reports.txt! #This logfile contains one entry per night of the survey giving breif info about night conditions! #Description of columns:! #Name Description! #----- -----------------------------------------------------------------------------! Night Number of this night (1st night=1)! JD_midnight Julian date at local midnight (decimal days of Julian epoch) ! JD_twi_eve Julian date at the end of evening twilight (days) ! JD_twi_morn Julian date at the beginning of morning twilight (days) ! JD_start Julian date at the beginning of survey (days) ! - Additional reports of adverse night conditions are appended to entry where applicable! #----- ----------- ------ --------------------------------------------------------------! Night 1/1827 JD_midnight= 2458485.62500 JD_twi_eve= 2458485.54306 JD_twi_morn= 2458485.85278 JD_start= 2458485.00000 : The cloud cover is too thick, closing dome all night, sorry!! Night 2/1827 JD_midnight= 2458486.62500 JD_twi_eve= 2458486.54375 JD_twi_morn= 2458486.85347 JD_start= 2458485.00000 : ! Night 3/1827 JD_midnight= 2458487.62500 JD_twi_eve= 2458487.54375 JD_twi_morn= 2458487.85417 JD_start= 2458485.00000 : ! Night 4/1827 JD_midnight= 2458488.62500 JD_twi_eve= 2458488.54375 JD_twi_morn= 2458488.85486 JD_start= 2458485.00000 : The cloud cover is too thick, closing dome all night, sorry!! Night 5/1827 JD_midnight= 2458489.62500 JD_twi_eve= 2458489.54375 JD_twi_morn= 2458489.85556 JD_start= 2458485.00000 : ! Night 6/1827 JD_midnight= 2458490.62500 JD_twi_eve= 2458490.54375 JD_twi_morn= 2458490.85556 JD_start= 2458485.00000 : The cloud cover is too thick, closing dome all night, sorry!! Night 7/1827 JD_midnight= 2458491.62500 JD_twi_eve= 2458491.54375 JD_twi_morn= 2458491.85625 JD_start= 2458485.00000 : The wind speed is too high, closing dome all night, sorry!! ! ! Night 181/1827 JD_midnight= 2458665.66700 JD_twi_eve= 2458665.47603 JD_twi_morn= 2458665.92047 JD_start= 2458485.00000 : We are going to carry out planned maintenance all night, sorry!! Night 182/1827 JD_midnight= 2458666.66700 JD_twi_eve= 2458666.47672 JD_twi_morn= 2458666.92047 JD_start= 2458485.00000 : We are going to carry out planned maintenance all night, sorry!! Night 183/1827 JD_midnight= 2458667.66700 JD_twi_eve= 2458667.47672 JD_twi_morn= 2458667.92047 JD_start= 2458485.00000 : ! Night 184/1827 JD_midnight= 2458668.66700 JD_twi_eve= 2458668.47672 JD_twi_morn= 2458668.92117 JD_start= 2458485.00000 : ! Night 185/1827 JD_midnight= 2458669.66700 JD_twi_eve= 2458669.47742 JD_twi_morn= 2458669.92117 JD_start= 2458485.00000 : ! Night 186/1827 JD_midnight= 2458670.66700 JD_twi_eve= 2458670.47742 JD_twi_morn= 2458670.92117 JD_start= 2458485.00000 : The wind speed is too high, closing dome all night, sorry!! Night 187/1827 JD_midnight= 2458671.66700 JD_twi_eve= 2458671.47742 JD_twi_morn= 2458671.92117 JD_start= 2458485.00000 :
Input catalogue, target density
Target density (per square degree)
ne 7000
a
pl
t ic
a c
al
G
4000
Galactic centreCompleted targets after five years
Target density (per square degree)
7000
4000Completed targets over five years
All surveys together
4FS - Survey completeness progress
DRS1 Low Resolution Milky Way Halo
1
DRS2 High Resolution Milky Way Halo
DRS3 Low Resolution Milky Way Disk Bulge
DRS4 High Resolution Milky Way Disk Bulge
DRS5 X-Ray Galaxy Clusters
DRS6 X-Ray AGN and QSO Survey
0.8 DRS7 Galaxy Evolution (WAVES)
DRS8 Cosmology
Completeness (Nsuccess/Ntotal)
0.6
0.4
0.2
0
0 200 400 600 800 1000 1200 1400 1600 1800
Day of surveyCompleted targets after five years
Survey subFoM progress - DRS3 Low Resolution Milky Way Disk Bulge
Survey FoM
1
subFoM: ESN
subFoM: DB1
subFoM: DB2
subFoM: DB3
subFoM: DB4
0.8
FoM, subFoM
0.6
0.4
0.2
0
0 200 400 600 800 1000 1200 1400 1600 1800
Day of survey
4MOST Facility Simulator - OpSimCompleted targets after five years
Survey subFoM progress - DRS3 Low Resolution Milky Way Disk Bulge
Survey FoM
1
subFoM: ESN
subFoM: DB1
subFoM: DB2
subFoM: DB3
subFoM: DB4
0.8
FoM, subFoM
0.6
Much work still to be done to optimize this process.
0.4
Eventually we must also include the surveys from the
community.
0.2
0
0 200 400 600 800 1000 1200 1400 1600 1800
Day of survey
4MOST Facility Simulator - OpSimHR disk and bulge
• ~3M objects
• Survey PIs: Thomas Bensby, Maria Bergemann
– MV > -5
– 14 < V < 16
20% error in distances
With disk-style
– error(distance)< 20%
for red giant stars (no
obscuration) obscuration – Evenly distributed
– 4.4~106 stars
– 800 000 in bulge
10% error for an
unobscured sun # of stars/103
Sun’s orbit
z (kpc)
r
ba
tic
lac
Ga
220 km s-1
Area obscured
300 million years
by Galactic core
x (kpc)4MOST ! Extragalactic science
!
!
• eROSITA galaxy clusters (~50,000 clusters, ~2.5M objects) Alexis Finoguenov
– Dark Energy and galaxy evolutions
• eROSITA AGN (~1M objects) Andrea Merloni
– Evolution of AGN and the connection to their host galaxies
• Galaxy evolution WAVES (~1.5M objects) Simon Driver, Joe Liske
– Dense magnitude/redshift limited galaxy survey
• Cosmology Redshift Survey (~23M objects) Francisco Kitaura, Johan Richard
– Luminous red, emission line galaxies to probe the nature of gravity and dark
energy4MOST ! analysis
Proposals
4MOST ESO
Phase 1 consortium community
Members ESO Public Survey Panel
Targets Members
Targets
Surveys, Priorities
Science
• With a data rate of ~45 000 spectraPhase 2
per night (perhaps 25 000 of stars) we need Team
Targets, Survey Strategy
an efficient machinery for data processing and analysis
OpSys
Observing Blocks
ESO OB database
Observing
‣! Relevant part of facility will become part
OBs valid for the night, Cal OBs
Night
Observation Tool
observer
! of operations OB to be executed
! ✴ Data management —> Data reduction
4MOST
ICS
Instrument
! ✴ Calibration system —> QC
Raw data (science, calibration)
! ESO data archive
! Raw data, Observing information
Data Reduction
‣ Building a robust set of analysis pipelines Spectral Reduction Data Analysis
✴ Stellar analysis pipeline (Lind, Kordopatis) Reduced spectra
Reduced spectra
✴ Extragalactic pipeline (Croom, Davies) Science
Reduction
4MOST archive
✴ Community can join these
High-level products
Reduced spectra
Phase 3 High-level products
Science4MOST science
• 5+5 year public spectroscopic survey starting 2021
• 15 million spectra for community proposals in 2018
• Gaia complement:
-13x106 , R~5000 mV~15-20 mag
-2x106 , R~20000 mV~14-16 mag
• eROSITA complement:
- 2 ×10 spectra of AGN and 50000 cluster galaxies
6
• Euclid/LSST/SKA… complement:
- >13 ×10 m ~20-22.5 mag LRGs and ELGs
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