QSO (AGN) study with PFS
Masa Imanishi
NAOJ/Subaru TelescopeWith help from
Masayuki Akiyama (Tohoku)
Yoichi Itoh (Kobe)
Toshihiro Kawaguchi (Tsukuba)
Tohru Nagao (Ehime)
science discussion inside HSC QSO teamQSO (AGN)

Type-1 QSO = brightType-1High S/N spectra
even at high-z
AGN-starburst connections
Feedback to host galaxies
Origin of galaxy downsizing?

<1pc

Energetically dominatedby mass-accreting
Supermassive blackhole(SMBH) (>107 Msun)

QSO science with PFS =follow-up spectroscopy of HSC-detected
QSO candidates
HSC wide survey : >1000 deg2 (g,r,i,z,y)g=26.3, r=26.0,
i=26.0, z=24.9,
y=23.8 (AB)g r i zy
4000
6000 10000A

1. numerous faintQSOs at z>3
2. z>6.7 QSOs

z>3 QSOs
QSO number density QSO number density
has a peak at z=2-3

z>3 = SMBH growing
phaseRichards+06

Important epoch tounderstand thecosmic evolution
of QSO phenomenon

SDSS found many QSOs only at z>3(i<20.1 for spectroscopy)

What is unknown about z>3 QSOs ?
Faint QSO LF at z>3Clustering properties of QSOs at z>3
Evolution of general SMBHs (108 Msun)
Metallicity in chemically immatured QSOsz>6.4 QSOs

HSC survey will bring a remarkable progress

HSC z~3-5 QSO (g,r,i-selection)g r i zyriz : z=4.6-5.1

rr’-—ii’ii’ -— zz’

gri : z=3.6-4.4

QSO
Richards+01

g’ — r’g-r

QSO

r’ — i’r-i

QSO LF SDSS : bright QSO LF only at z>3( i < 20.1 for spectroscopy )Richards+06

Understanding the faint end of QSO LF= origin of cosmic UV background radiation
Effect to subsequent galaxy formation

QSO-QSO clusteringz>3

clusteringz<2.2

Halo mass
QSO lifetime

S (h-1 Mpc)
Croom+05 (>20,000 QSOs)

35Enoki+03

SMBH evolution
LF

Constant L/L(Edd)assumedM(SMBH) andL/L(Edd) in
individual QSOs
How about moregeneral QSOs with
M(SMBH) <108 Mo ?
HSC

SMBH evolution(qualitative)

108.7 Mo

109 Mo109.7 Mo

1010 Mo

Kelly+10 (SDSS)

Cosmic chemical evolution

metallicity

Maiolino+08

Star-forming galaxies:
not applicable to z>3.5M(stellar)

QSOs

Cosmic chemical evolution (2)QSOs are bright
QSOs have metal emission lines in UV
Chemical evolution canbe probed at z>3.5
via optical spectroscopy
Modest luminosity QSOs
= chemically-immatured ?

Assumption about PFS
・ 1.5 deg2 FOV・ 3900-10800 A (extended to 13000A ?)・ 2400 fibers
・ R=30005σ (AB)

Sensitivity (by Dr. Iwata) (900sec, R=2500)

Wavelength (A)Number density of z=3-5.5 QSOs
Casey+0830-650 QSOs / deg2
numberi<24z=3-5.5100/deg2

LDDEPLECandidates = 50-2000 / deg2
18i=24

Survey strategy (z=3-5.5 QSOs)
LF, clustering
ID as z>3 QSOs (i<24, S/N>3-5,R~300-500)
1 hr, 75 deg2, <10 nights (LF)
1 hr, >400 deg2, >40 nights (clustering)
SMBH evolution
108 Mo at z=4
S/N>10 to estimate M(SMBH) i<22.5
1 hr, 400 deg2, ~35 nights
Chemical evolution
Weak metal lines i<23
2.5 hr, 150 deg2, ~35 nights

High-z =Longer λHSCg r i zy
8000A
10000A

350 z~6 QSOs(z<24.2)
Fan+06

8000A

9000A

35 z~7 QSOs(y<23.8)

z~7 QSO science
Currently, most distant QSO : z~6.4
Most distant, bright QSOs
Constraints on SMBH formation theory
z=25 : 100Mo BH Eddington growthz=6.5 :109 Mo

z=7.5 : 108 Mo

Study the physics (including neutral fraction)of more distant IGM with high S/NGalactic
BD

flux

High-z QSO and brown dwarf (BD)
Gradually
increase

flux

wavelength

High-z
QSO

Sharp gap

wavelengthz~7 QSO (z-dropout,y-detected)z-y>2.3 selection（remove BD）
z=24.9,y=22.6

g r i zy

In VIKING field (J=22.2)AB,z-y>1.7, y-J<1z=24.9,y=23.2(HSC: z=24.9,y=23.8)

z-yz~7 QSOBDy-JKashikawa10

Many faint z~6 QSO
z~6 IGM study inmany sightlines(neutral fractionincreases?)τ(GP)z~6 QSO science

i=26.0,z=24.2,y=23.8

4

5Fan+066

z~7 QSOs (z-dropout,y-detected)
35 z~7 QSOs should be includedin HSC wide 1000 deg2 (y<23.8)
We can select only 10 z~7 QSOs (from BDs)(y<23.2) via Subaru FOCAS spectroscopy
How about remaining 25 z~7 QSOs ?
PFS spectroscopy of z-dropout sources(z>24.9, y=23.2-23.8)
2.5hr, >500 deg2, >100 nights<10 candidates / PFS FOV

z~6 QSOs (i-dropout, z-detected)
Impossible to spectroscopically
identify 350 z~6 QSOs (z<24.2)
with Subaru FOCASPFS spectroscopy of i-dropout sources(i>26.0, z<24.9)
2.5hr, >500deg2, >100 nights<10 candidates / PFS FOV

Brown dwarf (BD) science
PFS spectroscopy (z<22.6) of HSC-widearea will find 500 BDs
Stellar IMF inBD regime
2.5hr, >500 deg2,>100 nights<10 candidates / PFS FOV

Chabrier+03

BD

Summary1hr, 400 deg2, 40 nights
LF, clustering, SMBH evolution
of QSOs at z=3-5.5
50-1000 / PFS FOV
2.5hr, >500 deg2 (?), >100 nights
Chemical evolution, z>6 QSOs, BD<500 / PFS FOV
Combined with 4hr, 300 deg2
galaxy survey ?

Request for PFS specificationand survey design
High sensitivity at >8000A
Wide wavelength coverage (3900-10800A)
A wider FOV (>1.5 deg2) may help
2400 fibers and R=3000 are sufficient
Target field must be HSC wide

HSC+PFS is most powerful until
LSST (and subsequent follow-upspectroscopy) start operation
TMTSpectroscopy of z>6 QSOs to study IGM
ALMAgas of QSO host galaxies
WFIRST/WISH
Numerous fainter z>7 QSOs

Other potential QSO science with PFS・ Obscured AGNs (via galaxy survey)
Type-2・ z<3 QSOs (u-band available ?)・ Ly alpha forest toward z<3 QSOs
・ variability-selected low-L AGN (deep)
Other people’s talkIf z>3 QSO number per PFS FOV is << 2400,z<3 PFS QSO science should be combined

Endz~7 QSO

Number of faint QSOs :Smaller than previously expected

HSC/wide（z~7）
Jiang+09

faintM1450A brightg r i zy

Selectable z~7 QSO:
7/1000 deg2
12（VIKING）（conservative）
Lim-mag:(z,y) = (24.9, 23.8) AB
z~7 QSOs included
in y-band : ~35/1000deg2

Selection z-y>1.5

PFS（z~7 QSO）
Follow-up spectroscopy of HSC z~7 QSOcandidates
Several 10s candidates/1000 deg2
Use extra several fibers
in other galaxy surveys
At least cover Lyα : 9000 - 10500A
High sensitivity required
SMBH mass
IGM physics

MOIRCSTMT2. z~6 QSO (i-dropout, z-detected)
i-z red（>1.8）：by IGM absorption
z-y blue（<0.5）：BD removal

g r i zy

HSC/wide（z~6）
Jiang+09

350/1000 deg2（conservative）
Selection :i=26.0,z=24.2, y=23.8(AB)faintM1450A brightPFS（z~6 QSO）
Follow-up spectroscopy of HSC z~6 QSOcandidates
1000 candidates/1000 deg2 （1/deg2）
Use extra several fibers
in other galaxy survey
At least cover Lyα : 8000 – 9000A
High sensitivity requiredz~6 IGM multiple sightlines

TMT