Formation and evolution of SMBHs

revealed by 'Wide field', 'Multi-wavelength', and 'Transient' surveys with HSC

 

We are pleased to announce a conference entitled "Formation and evolution of SMBHs revealed by 'Wide field', 'Multi-wavelength', and 'Transient' surveys with HSC" held on 2nd-3rd November 2018 in Sendai, Japan.
# This is a full two-days conference (it would start at ~9:00 on Nov.2nd and finish at ~ 17:00 on Nov. 3rd).

Scientific Rationale

 

The formation and evolution of supermassive black holes (SMBHs) are among the most exciting and challenging topics in astronomy and astrophysics. New wide-field deep surveys using Subaru Hyper Suprime-Cam (HSC) will bring promising opportunities to make breakthroughs in this research field.
The HSC Subaru Strategic Program has started in 2014, collaborating with Taiwan, Princeton, and Japan.We have completed two thirds of allocated observations, providing deep multi-band photometry for about 350 square degrees. Also, the HSC-SSP data that covers 100 square degrees have been released to the public last year.
Now it is a good opportunity to share what we learn from HSC-SSP data and to discuss how to accelerate AGN sciences with HSC.

We plan to have the following topics:

  • What is HSC-SSP? How to join this collaboration?
  • Sharing the current status of the HSC-SSP and available dataset
  • AGN sciences with wide field survey
  • AGN sciences with multi-wavelength dataset
  • AGN sciences with transient/variability
  • Theoretical models and comparison with HSC data
  • Collaborations with future surveys

 
Note that this meeting is not closed for current member of the HSC-SSP.
New participants who have not yet used the HSC data but are interested in AGN sciences with HSC are highly welcome!

Confirmed Invited Speakers

 

  • Dani Chao (MPA)
  • Andy Goulding (Princeton Univ.)
  • Wanqiu He (Tohoku Univ.)
  • Hiroyuki Ikeda (NAOJ)
  • Taiki Kawamuro (NAOJ)
  • Mitsuru Kokubo (Tohoku Univ.)
  • Yoshiki Matsuoka (Ehime Univ.)
  • Tomoki Morokuma (Univ. of Tokyo)
  • Takashi Moriya (NAOJ)
  • Hikari Shirakata (Hokkaido Univ.)
  • Kazuyuki Sugimura (Tohoku Univ.)
  • Hisakazu Uchiyama (SOKENDAI)
  • Takuji Yamashita (Ehime Univ.)

Schedule

 

DAY 1 (Nov. 2nd)

 

09:00-09:05

Opening remark

Yoshiki Toba (Kyoto Univ.)

09:05-09:10

LOC announcements

Masayuki Akiyama (Tohoku Univ.)

 

◆ Session 1: "Wide-field" survey with HSC      Chair: Tomoki Morokuma

09:10-09:35

Current status of HSC-SSP and activities of the HSC-AGN consortium (25)

Tohru Nagao (Ehime Univ.)

09:35-10:00 

HSC Pipeline and Database (25)

Hiroyuki Ikeda (NAOJ)

10:0010:25

Probe the mass function and Eddington-ratio distribution of low-luminosity quasars at z=4 (25)

Wanqiu He (Tohoku Univ.) 

10:25-10:40  

The faint-end of the quasar luminosity function at z~5 with the HSC-SSP survey (15)

Mana Niida (Ehime Univ.)

10:40-11:00

Coffee break (20)

11:0011:25

SHELLQs: approaching 100 new quasars at z > 6 (25)

Yoshiki Matsuoka (Ehime Univ.) 

11:25-11:50

Luminous quasars do not live in the most overdense regions of galaxies at z~4 (25)

Hisakazu Uchiyama (SOKENDAI)

11:50-12:05

The UV luminosity function of reselected high-z AGNs in the COSMOS field (15)

Karin Shimodate (Univ. of Tokyo) 

12:05-12:25

Discussion (Yoshiki Toba)

12:25-13:00

Poster talks (35)

1. The 105-month Swift-BAT all-sky hard X-ray survey (4)

Kyuseok Oh  (Kyoto Univ.)

2. X-Ray Spectral Model from Clumpy Torus and Its Application to Circinus Galaxy (4)

Atsushi Tanimoto (Kyoto Univ.)

3. Broadband X-Ray Spectral Analysis of Two Seyfert 1 Galaxies (IC 4329A and NGC 7469) with Clumpy Torus Model (4)

Shoji Ogawa  (Kyoto Univ.)

4. ”Dual-NB" emitters: A new wide-field search for high-z obscured AGNs (4)

Kohei Iwashita (Ehime Univ.)

5. Detections of [OIII] 88 micron in Two Quasar Host Galaxies in the Reionization Epoch (4)

Takuya Hashimoto (Osaka Sangyo Univ., NAOJ)

6. Environment and activity of a hyperluminous QSO revealed by HSC NB imaging (4)

Satoshi Kikuta (SOKENDAI)

7. A systematic search for the hidden AGN in optically faint ULIRGs from AKARI catalog (4)

Xiaoyang Chen (Tohoku Univ.)

8. Clustering of optical and X-ray AGN in a semi-analytic model (4)

Taira Oogi (Kavli IPMU)

9. X-ray properties of z=4 HSC quasars (4)

Masayuki Akiyama (Tohoku Univ.) 

13:00-14:30 

Lunch

 

◆ Session 2: "Transient" survey with HSC      Chair: Masahiro Nagashima

14:30-14:55

HSC SSP transient survey (25)

Takashi Moriya (NAOJ)

14:55-15:20 

Time-domain studies of AGN/quasar optical variability with HSC-SSP (25)

Mitsuru Kokubo (Tohoku Univ.)

15:20-15:35

Tidal Disruption Events in HSC-SSP Transient Surveys (15)

Tomoki Morokuma (Univ. of Tokyo)

15:35-15:55

Coffee brak (20)

15:55-16:20

Search of strongly lensed quasars via variability with HSC-SSP transient survey (25)

Dani Chao (MPA)

16:20-16:40

Discussion (Tomoki Morokuma) 

16:40-17:40

Poster session

18:00-

Banquet @Espace Uvert

(Faculty: 5000 JPY/ Postdoc: 3000 JPY/ Student: 2000 JPY) 

 
 

DAY 2 (Nov. 3rd)

 

◆ Session 3: "Multi-wavelength" data with HSC      Chair: Nobunari Kashikawa

09:00-09:25

A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS) (25)

Takuji Yamashita (Ehime Univ.)

09:25-09:40

Multi-Wavelength properties of the HSC-FIRST radio galaxies/quasars (15)

Yoshiki Toba (Kyoto Univ.)

09:40-09:55

Extremely radio-loud AGN residing in low-mass galaxies discovered by HSC survey (15)

Kohei Ichikawa (Tohoku Univ.)

09:55-10:20

The demography of infrared-selected AGN in HSC-SSP (25)

Andy Goulding (Princeton Univ.)

10:20-10:35

Discovery of blue-excess dust-obscured galaxies by using Subaru Hyper Suprime-Cam (15)

Akatoki Noboriguchi (Ehime Univ.)

10:35-10:55 

Coffee break (20)

10:55-11:10

SHELLQs-ALMA: submm follow-up of less-luminous quasars (15)

Takuma Izumi (NAOJ)

11:10-11:25

Detecting the underlying host galaxies of SDSS QSOs at z < 1 with HSC (15)

John Silverman (Kavli IPMU)

11:25-11:40

Rapidly Growing Supermassive Black Hole in the Merging Galaxy Mrk 463 (15)

Satoshi Yamada (kyoto Univ.)

11:40-12:00

Discussion (Masayuki Akiyama) 

12:00-13:30

Lunch

 

◆ Session 4: "Theoretical model" with HSC      Chair: Yoshiki Toba

13:30-13:55

Modeling galaxy and AGN formation in the CDM universe (25)

Masahiro Nagashima (Bunkyo Univ.)

13:55-14:20

Forthcoming collaborations between HSC data and theoretical models (25)

Hikari Shirakata (Hokkaido Univ.)

14:20-14:45

Formation of SMBHs in the early Universe: theoretical perspective (25)

Kazuyuki Sugimura (Tohoku Univ.)

14:45-15:05

Coffee break (20)

15:05-15:25

Discussion (Keiichi Wada)

 

◆ Session 5: "Future synergy" with HSC      Chair: Takuma Izumi

15:25-15:40

AGN sciences with PFS (15)

Tohru Nagao (Ehime Univ.) 

15:40-16:05

HSC and eROSITA AGN Study from an X-ray Perspective (25)

Taiki Kawamuro (NAOJ) 

16:05-16:25

Coffee break (20)

16:25-17:05

Discussion/closing remarks (Tohru Nagao)

Abstract

 

◆ Session 1: "Wide-field" surveys with HSC


Current status of HSC-SSP and activities of the HSC-AGN consortium

Tohru Nagao

 

I would like to review the current status of the HSC-SSP survey. Then I would show the recent activities of the HSC-AGN consortium for clarifying what we have achieved so far and what we should achieve in the next step.


HSC Pipeline and Database

Hiroyuki Ikeda

 

I will talk about the latest version of the HSC pipeline and the database.


Probe the mass function and Eddington-ratio distribution of low-luminosity quasars at z=4.

Wanqiu He

 

Cosmological evolution of the black hole mass function (BHMF) and Eddington ratio distribution function (ERDF) at z > 3 are the main demographic constraints to statistically unveil the growth history of SMBHs in the early universe. The wide and deep imaging of the HSC-SSP enables us to select a large sample of z=4 quasars around the knee of the luminosity function, i.e., the typical quasars at the epoch. We conducted the spectroscopic follow-up of the quasar sample with the AAT/AAOmega to estimate their black hole masses and Eddington ratios through the CIV emission line. Utilizing the 45 identified z~4 quasars at 20<i<22.5, which are ~2 mag fainter than the SDSS luminous quasars, we derived the flux-limit corrected z=4 BHMF and ERDF with a reliable constraint (>10% completeness) at M_{BH}>10^{7.8} and \lambda_{Edd}>0.1. Different from previous studies suggesting a fast growth of the high-redshift quasars accreting at the Eddington limit, the newly derived z = 4 ERDF shows an increasing trend toward the low Eddington-ratio end, implying a large fraction of SMBHs at z = 4 are already “quiescent”.


The faint-end of the quasar luminosity function at z~5 with the HSC-SSP survey

Mana Niida 

 

The quasar luminosity function (QLF) provides us a clue to understand the evolution of supermassive black holes and the history of cosmic reionization. Recent studies have derived QLFs at various redshifts over a wide luminosity range. They have suggested that the redshift evolution of the quasar number density is luminosity-dependent. However, the low-luminosity quasar number density at z>4 is unclear due to insufficient area and sensitivity in past surveys. Therefore we are trying to search for low-luminosity quasars at z~5 with using the wide and deep survey data in a part of the Subaru strategic program with Hyper Suprime-Cam (HSC). We selected candidates of low-luminosity quasars at z~5 by adopting the so-called Lyman-break method. As the result, we obtained a large sample of quasar candidates at z~5 with a luminosity range of -27.4<M_1450<-22.4. We derived the QLF at z~5 taking into account of the survey completeness and the contamination of Galactic stars and galaxies. As the result, the faint-end slope of our QLF is flatter than that of previous studies. This is not consistent with the result of Giallongo et al. (2015) which indicates that quasars are possibly main contributor to the cosmic reionization. Our trend is consistent with the z~4 QLF using HSC data (Akiyama et al. 2018). In this presentation, I would like to discuss also the redshift evolution of quasar number density.


SHELLQs: approaching 100 new quasars at z > 6

Yoshiki Matsuoka

 

High-redshift (z > 6) quasars are a unique probe of the distant Universe, for understanding the formation of supermassive black holes, the early evolution of the host galaxies, and the origin and progress of the cosmic reionization. We are carrying out a spectroscopic survey for high-z quasars based on the HSC-SSP survey data, and have so far discovered ~80 new quasars at 5.8 < z < 7.1. I will report the progress and some recent results of the project.


Luminous quasars do not live in the most overdense regions of galaxies at z~4

Hisakazu Uchiyama

 

We present the cross-correlation between luminous quasars and  protocluster candidates at z~4, extracted from the Wide imaging survey performed with a part of HSC-SSP. We find that only two out of 151 quasars reside in regions that are more overdense compared to the average field at >4σ.   The distributions of the distance between quasars and the nearest protoclusters and the significance of the overdensity at the position of quasars are statistically identical to those found for LBGs, suggesting that quasars tend to reside in almost the same environment as star-forming galaxies at this redshift. Using stacking analysis, we find that the average density of LBGs around quasars is slightly higher than that around LBGs on 1.0-2.5 pMpc scales, while at <0.5 pMpc that around quasars tends to be lower. We also find that quasars with higher UV-luminosity or with more massive black holes tend to avoid the most overdense regions, and that the quasar near zone sizes are anti-correlated with overdensity.  These findings are consistent with a scenario in which the luminous quasar at z~4 resides in structures that are less massive than those expected for the progenitors of today's rich clusters of galaxies, and possibly that luminous quasars may be suppressing star formation in their close vicinity.


The UV luminosity function of reselected high-z AGNs in the COSMOS field

Karin Shimodate

 

Ionizing photon sources that caused the cosmic reionization is considered to be a star forming galaxies (SFGs) or an active galactic nucleus (AGNs), but it has not been clarified yet. The goal of this study is to constrain the contribution of AGNs to the cosmic reionization. As a first step, we reselected z~4 AGNs in the Cosmic Evolution survey (COSMOS) field and investigated QSO UV luminosity function. AGNs are selected by crossmatching dropout catalog with X-ray, radio catalog or by color selection based on multi-wavelength observation data. Then, their UV luminosity function is calculated. From our results, it is suggested that AGNs could be main contributors to the cosmic reionization. 


 
 

◆ Session 2: "Transient" data with HSC


HSC SSP transient survey

Takashi Moriya

 

I will overview the HSC transient survey conducted in the HSC SSP.


Time-domain studies of AGN/quasar optical variability with HSC-SSP

Mitsuru Kokubo

 

Optical variability is an ubiquitous property of AGNs/quasars, and time-domain studies of the AGN/quasar variability enable us to probe fundamental physics of the AGN/quasar accretion disks. Subaru/HSC-SSP survey produces multi-epoch, multi-band photometry for hundreds of high-redshift quasars with unprecedented photometric accuracy. In this talk I will briefly introduce some examples of studies enabled with the time-domain HSC-SSP data.


Tidal Disruption Events in HSC-SSP Transient Surveys

Tomoki Morokuma

 

Tidal disruption events are transient phenomena where stars accidentally coming close to central supermassive black holes are gravitationally disrupted.  We are conducting HSC-SSP transient surveys in COSMOS and SXDS fields. We have already finished the 1st consecutive 6-month survey in COSMOS. We found several candidates of tidal disruption events and made follow-up observations for some of the candidates in addition to archival studies on the objects. I will introduce the current status of the HSC-TDE studies. 


Search of strongly lensed quasars via variability with HSC-SSP transient survey

Dani Chao

 

Strongly lensed quasar is a powerful astrophysical and cosmological probe to study, for example, mass distribution of the foreground galaxy, host galaxy of quasar, variability of quasar, and the expansion of the Universe. However, lensed quasars are rare, and in the present stage, we need to increase the number of lensed quasars for scientific studies. There is a known lensed quasar in the COSMOS field of the Hyper Suprime-Cam (HSC) transient survey, which shows the potential of discovering new lensed quasars from the HSC transient survey through their variable nature. In this talk, I would like to present our development of a lens search algorithm that is variability-based. I will present how we build the algorithm by simulating mock lensed quasars with realistic effects from the HSC transient survey, such as the point-spread function (PSF), the cadence, and the subtraction through the transient pipeline. I will also describe our plans of testing the algorithm on the HSC difference images and applying the algorithm to discover new lensed quasars in the HSC transient survey. If time allows, I will mention some of the work about finding lensed supernovae.


 
 

◆ Session 3: "Multi-wavelength" data with HSC


A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS)

Takuji Yamashita

 

We will present the current status of our on-going projects, “A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS)”. Radio galaxies are an important population for understanding the evolution of galaxies and SMBHs. The previous SDSS samples of radio galaxies were limited to optically bright objects (i < 21) and local objects (z < 0.5). Our WERGS project allows us to study the evolution of radio galaxies beyond local universe and faint rare sources, taking advantage of wide (~1400 square degree) and deep (i < 26) HSC imaging. The initial result using HSC-SSP and FIRST radio catalogs are published in Yamashita et al. (2018). The photometric redshifts of the HSC-FIRST radio galaxies are beyond z = 1. It was found that optically-faint and blue-color radio galaxies have relatively young stellar populations compared to local classical radio galaxies and increase in number up to z ~ 1 (Yamashita et al. in prep.). Currently, we are addressing a broad multi-band SED fitting analysis, including infrared photometries (Toba et al. in prep.). The WERGS HSC-FIRST sample includes rare radio galaxies with extremely high radio-loudness and low stellar-mass, which could be candidates of rapidly growing SMBHs (Ichikawa et al. in prep.). In this talk, we will introduce our project and review a picture of radio galaxies revealed by WERGS.


Multi-Wavelength properties of the HSC-FIRST radio galaxies/quasars

Yoshiki  Toba

 

We present physical properties of optically-faint (i_AB > 21.3) radio galaxies/quasars newly discovered by Subaru Hyper-Supreme Cam (HSC) and VLA Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. For 3579 objects detected by HSC and FIRST in Yamashita et al., we compiled multi-wavelength data of optical, near-infrared (IR), mid-IR, far-IR, and radio (150 MHz). We derived their color excess (E (B-V)), stellar mass, star formation rate (SFR), IR luminosity, the ratio of far-IR and radio luminosity, and radio spectral index that are derived from the Spectra Energy Distribution (SED) fitting. We fount that optically-faint radio galaxies/quasars show a large dust extinction, low stellar mass, high SFR and AGN luminosity compared to optically-bright ones (Toba et al. 2018 in prep.).


Extremely radio-loud AGN residing in low-mass galaxies discovered by HSC survey

Kohei Ichikawa

 

We present the optical and infrared properties of extremely radio-loud AGN residing in the low-mass galaxies. Recent Subaru/HSC strategic survey revealed optically-faint radio galaxies (RG) down to g~26, opening the new parameter space of extremely radio-loud AGN with radio-loudness parameter of log R = log (f_{1.4 GHz}/f_g) >4, and we call them extremely radio-loud galaxies (ERGs). ERGs were undetectable in the previous SDSS surveys because of their shallow sensitivity. ERGs show completely different properties compared to the conventional RGs. (1) ERGs follow SF main-sequence. (2) Using the conversion of M* into BH mass M_BH by Reines & Volonteri (2015), we roughly be able to measure the Eddington luminosities LEdd for our sample. Combining the infrared catalog information (Toba et al. in prep.), ERGs show high L_12um/LEdd with -1< log L12um/LEdd<1, suggesting that ERGs might be in the super-Eddington accretion phase. (3) By limiting the sample at z<1, ERGs reside in low-mass galaxies with log (M*/Msun)<10. Therefore, low-z ERGs are prominent candidates of very rapidly growing black holes with super-Eddington accretion before the feedback process is in place.


The demography of infrared-selected AGN in HSC-SSP

Andy Goulding

 

Active galactic nuclei (AGN) that are identified using multiwavelength analyses can provide a relatively obscuration-independent view of the population of growing supermassive black holes. I will discuss our recent efforts to combine HSC-SSP with mid-infrared data from the WISE all-sky survey to build a large unbiased sample of quasars for galaxy evolution studies. This was achieved through a suite of machine learning techniques that we developed to measure their redshifts, AGN type, and host-galaxy interaction stages. Using these datasets we are now mapping the growth of BHs from z~1, investigating AGN triggering mechanisms, and assessing their connection to large-scale structure.


Discovery of blue-excess dust-obscured galaxies by using Subaru Hyper Suprime-Cam

Akatoki Noboriguchi

 

In this presentation, we report our discovery of "blue-excess" dust-obscured galaxies (BluDOGs). DOGs are faint in optical but very bright in mid-infrared (mid-IR), which are powered by active star-formation or AGN, or both. DOGs are believed to be a candidate population that are evolving to quasars from gas-rich mergers. On the other hand, a few hot dust-obscured galaxies (Hot DOGs) whose dust temperatures are higher than usual dust-obscured galaxies show a "blue excess" in optical bands. The blue-excess is thought to be leaked AGN light. However, the nature of this blue-excess feature and the evolutionary picture of BluDOGs are observationally unclear. By combining three multi wavelength catalog of optical (Subaru HSC), near-IR (VIKING), and mid-IR (ALLWISE), we have discovered 571 DOGs. By studying the spectral energy distribution in optical, we found that a few DOGs shows an extremely blue color. The possible origins of this blue excess are the leaked AGN light and/or stellar UV light from a nuclear starburst. We discuss a possibility that the bluDOGs are in the transition phase from obscured AGNs to unobscured AGNs.


SHELLQs-ALMA: submm follow-up of less-luminous quasars

Takuma Izumi

 

We present our ALMA Cycle 4 + 5 submm follow-up studies of z > 6 less-luminous HSC quasars. Unlike the previously known optically-luminous quasars, host galaxies of those HSC quasar are FIR faint with LIRG-class star-formation activities (e.g., SFR ~ 10s Msun/yr). Indeed, [CII]/FIR ratios of our HSC quasars are consistent with the typical value of local normally star-forming galaxies. Meanwhile, ([CII]-based) dynamical masses of these HSC quasars are fully comparable to those of luminous quasars. These facts place our HSC quasars on the star-forming main sequence at z ~ 6 or even below it, implying that most of them represent a transition phase from a starbursting luminous quasar to a quiescent galaxy. We also found that the black hole mass to galaxy’s dynamical mass ratios of our HSC quasars are consistent with the local co-evolution relationship, manifesting that this relation was already established at z > 6. This immediately requires a very rapid galaxy/SMBH evolution mechanism such as expected in the standard merger-induced scheme.


Detecting the underlying host galaxies of SDSS QSOs at z < 1 with HSC

John Silverman

 

We will present preliminary results on the use of the publicly-available tool, Lenstronomy, to decompose HSC images of SDSS QSOs at z < 1 to detect the host galaxy. We will discuss plans to measure the stellar mass and star formation rate of the underlying host galaxies and compare to higher redshift studies with HST.


Rapidly Growing Supermassive Black Hole in the Merging Galaxy Mrk 463

Satoshi Yamada

 

Observations of dual AGN systems give us important information on the role of major mergers in black hole growth. Here we present a broadband (0.4-70 keV) X-ray spectral analysis of the merging galaxy Mrk 463, which contains dual AGNs (Mrk 463E and Mrk 463W) with a spatial separation of ~3.8 kpc. Both AGNs are obscured with hydrogen column densities of 8 x10^23 cm-2 and 3 x 10^23 cm-2, respectively. Comparing the X-ray luminosity with the L'-band (3.8 um), [O IV] 25.89 um, and [Ne V] 14.32 um ones, we find that Mrk 463E has an intrinsically X-ray weak AGN relative to its bolometric luminosity. Our results suggest that the black hole is rapidly growing, but is not deeply "buried" by circumnuclear dust unlike those in much later-stage mergers such as ultra-luminous infrared galaxies. Finally, we present prospects for studies of AGNs in merging galaxies using the joint e-ROSITA/HSC survey data.

 
 

◆ Session 4: "Theoretical model" with HSC


Modeling galaxy and AGN formation in the CDM universe

Masahiro Nagashima

 
We review the basics of our semi-analytic model of galaxy and AGN formation in the CDM universe. The model consists of merger trees of dark matter halos, gas cooling/heating processes, star formation and supernovae, galaxy mergers, stellar population synthesis technique, and so on. We show that the model reprodeuces many observational results such as luminosity functions and that it is useful to interpret observational results of galaxy and AGN surveys.


Forthcoming collaborations between HSC data and theoretical models

Hikari Shirakata

 

The data brought by the HSC-SSP should enable us to obtain more stringent constraints on the evolution of SMBHs and their host galaxies. Moreover, the comparisons of the data with the predictions from theoretical models should also play a crucial role. In this talk, I will show the latest results obtained with a semi-analytic model of galaxy formation, “New Numerical Galaxy Catalogue”. We have investigated the effect of the observational sample limitation on the Eddington ratio distribution function. Interestingly, the Eddington ratio distribution function estimated from shallow observational data has s steep slope than that predicted with theoretical models; such observational studies would undervalue the importance of the super-Eddington growth phase of SMBHs. It suggests the importance of the deep observations for understanding the evolution of SMBHs. Also, I briefly introduce the recent progress of cosmological simulations (with hydrodynamics or semi-analytics), and I want to stress the degenerate of the modellings of SMBHs and their host galaxies. I will propose the observational information which can be obtained by HSC-SSP to solve these degenerates.


Formation of SMBHs in the early Universe: theoretical perspective

Kazuyuki Sugimura

 

I will review the current status of theoretical understanding of SMBH formation in the early Universe, with focus on formation of SMBH seeds and their early growth. The SMBH seeds are often supposed to be either stellar remnants BHs with M_BH < 10^3 M_sun or direct collapse BHs with M_BH ~ 10^5 M_sun. I will discuss advantage and disadvantage of each scenario based on the current understanding.


 
 

◆ Session 5: "Future synergy" with HSC


AGN sciences with PFS

Tohru Nagao

 
The next generation prime-focus spectrograph (PFS) of the Subaru telescope will start its operation soon, probably in FY2021. By utilizing this gigantic spectrograph, a new Subaru Strategic Program (SSP) will be carried out, in which HSC-W and HSC-D fields will be observed. This is a great opportunity for AGN scientists, and thus I would like to share the current status of the PFS survey design with HSC-AGN colleagues. This talk is mostly for free discussion, where we will discuss various possibilities that can be done with the PFS-SSP survey.


HSC and eROSITA AGN Study from an X-ray Perspective

Taiki Kawamuro

 

Studying growing supermassive black holes (SMBHs) of AGN and their association with the host galaxies has been an attractive topic and intensively conducted so far. The HSC survey has provided us with large AGN samples, giving insights into un-obscured AGN luminosity functions (LFs) at high redshifts, host galaxy properties, and interesting but rare AGN populations, combined with surveys at other wavelengths (e.g., infrared (IR) and radio). In the next year of 2019, an observatory of eROSITA will be operated, and complement the X-ray band. Particularly in the initial PV-phase, the eFEDS (eROSITA Final Equatorial-Depth Survey) is planned to reach the same average depth of the 4-year eROSITA all-Sky survey over a 180 deg^2 area, located within the HSC survey region. X-rays are one of the most direct probe of the accretion processes, and penetrate through large columns of obscuring gas and dust. Also, they are less contaminated by stellar populations. Thus, the additional eROSITA X-ray data will make it possible to detect AGN missed because of the obscuration, and unveil those outshined by the host galaxy at other bands. Then, identifying galaxies of the eROSITA  AGN using the HSC, we will be able to discuss more un-biased LFs as well as investigate host galaxy properties of the AGN missed before. In this talk, I will present a brief summary of eROSITA as well as the eFEDS, and then introduce possible AGN scientific topics related to the above, including projects already proposed.


 
 
 

◆ Poster Presentation


X-Ray Spectral Model from Clumpy Torus and Its Application to Circinus Galaxy

Atsushi Tanimoto

 

We construct an X-ray spectral model from a clumpy torus in an active galactic nuclei (AGN), utilizing the Monte Carlo simulation for Astrophysics and Cosmology framework (MONACO: Odaka et al. 2016). The geometry of the torus is the same as that in Nenkova et al. (2008), who adopted a power law distribution in the radial direction and a normal distribution in the angular direction. We investigate the dependence of the X-ray continuum shape and Fe-K fluorescence line profile on the torus parameters. We compare our model with other torus models, such as MYTorus model (Murphy & Yaqoob 2009), Ikeda torus model (Ikeda et al. 2009), and CTorus model (Liu & Li 2014). Finally, we apply our model to the broadband X-ray spectra of the Circinus galaxy observed with Chandra, XMM-Newton, Suzaku, and NuSTAR, and discuss the results in comparison with the observations in other wavelengths.


The 105-month Swift-BAT all-sky hard X-ray survey

Kyuseok Oh

 

We present a new catalog of hard X-ray sources detected in the first 105 months of observations with the Burst Alert Telescope (BAT) on board the Neil Gehrels Swift observatory. The 105 month Swift-BAT survey is a uniform hard X-ray all-sky survey performed in the 14−195 keV band. The Swift-BAT 105 month catalog provides 1632 (422 new detections) hard X-ray sources in the 14 - 195 keV band above the 4.8 sigma significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert AGN in nearby galaxies (z < 0.2). The majority of the remaining identified sources are X-ray binaries (7%, 31) and blazars/BL Lac objects (10%, 43). As part of this new edition of the Swift-BAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105 month Web site.


Broadband X-Ray Spectral Analysis of Two Seyfert 1 Galaxies (IC 4329A and NGC 7469) with Clumpy Torus Model

Shoji Ogawa

 

We report the first results applying the X-ray clumpy torus model (XCLUMPY: Tanimoto et al., this conference) to type-1 active galactic nuclei (AGNs).  First, we investigate dependences of predicted iron-K equivalent width on torus parameters: hydrogen column density, torus angular width, and inclination angle. The intensity of the narrow iron-K fluorescence line can be used to infer the torus geometry, even in type-1 AGNs, which show no line-of-sight absorption. Then, we apply our model to the broadband X-ray data of two Seyfert 1 galaxies (IC 4329A and NGC 7469), and constrain their torus parameters by decoupling multiple spectral components. Finally, we compare the results with those obtained from infrared observations.


"Dual-NB" emitters: A new wide-field search for high-z obscured AGNs

Kohei Iwashita

 

We report the initial results of our study about a new method to search for high-z type-2 AGNs by utilizing the HSC NB data. It is important to study SMBHs and their evolution for understanding the evolutionary link between SMBHs and galaxies. For tackling this issue, it is crucial to carry out AGN surveys with a high completeness. However, optical broad-band color selection and variability-based selection are incomplete for obscured (i.e., type-2) AGNs. Sensitive hard X-ray surveys can detect type-2 AGNs, but they are not powerful for systematically survey of type-2 AGNs due to their small survey area. Here we would like to propose that a combination of two filters, NB718 and NB921 equipped in HSC can be powerful to search for high-z type-2 AGNs systematically, because these filters can detect Ly(alpha) 1216 and CIV1549 of emission-line galaxies at z ~ 4.9. The strong CIV emission is not seen in star-forming galaxies, so we can search for AGNs at z~4.9 by selecting objects that shows flux excesses in both NB718 and NB921. We have selected 33 objects which show NB718 and NB921 flux excesses simultaneously (hereafter `dual emitters'), by combining the catalogs of the HSC-SSP and CHORUS projects. The two objects among them show significant r-dropout features, meaning that they are high-z objects. In this poster, we report more detailed method and discussion about the dual emitters.


Detections of [OIII] 88 micron in Two Quasar Host Galaxies in the Reionization Epoch

Takuya Hashimoto

 

With ALMA, we report the detections of the [OIII] 88 micron line and dust continuum at 87 micron in the two quasar host galaxies in the reionization epoch, J2054-0005 at z = 6.0391 and J2310+1855 at z = 6.0035. The [OIII] luminosity of J2054-0005 and J2310+1855 are ~ 6.8e+9 Lsun and 2.4e+9 Lsun, respectively. Combining these [OIII] luminosities with the [CII] 158 micron luminosities in the literature, we find that J2054-0005 and J2310+1855 have the [OIII]-to-[CII] luminosity ratio of ~ 2.1 and 0.3, respectively, the latter being the lowest value among objects so far reported at z > 6. The high (low) luminosity ratio in J2054-0005 (J2310+1855) would be due to the stronger (weaker) UV radiation field as inferred from the high (low) dust temperature, ~ 50 K (37 K). Our results highlight the potential use of [OIII] as a tracer of the interstellar medium of high-z quasar host galaxies.


Environment and activity of a hyperluminous QSO revealed by HSC NB imaging

Satoshi Kikuta

 

In this poster, I present the recent results of our HSC observations for a hyperluminous QSO at z=2.85 to show what can be learned from wide-field imaging around QSOs. With narrow-band filter NB468, we detected 3490 Lyman alpha emitters (LAEs) around the QSO on degree scales. The QSO is found to be at the very center of a massive protocluster and the node of the cosmic web. Around the QSO are Mpc-scale diffuse Lyman alpha nebulae, making the one around the QSO the largest Lyman alpha nebula reported to date. Also, by assuming LAEs with high Lyman alpha equivalent width (>240) are illuminated by the central QSO and using a light echo, radiative history of the QSO can be traced. Their distribution suggests that the QSO was active 10 Myr and 45 Myr ago for about 10 Myr. These results demonstrate the potential usefulness of wide-field HSC NB data for luminous QSOs; it enables us to study large-scale environments and past activity of QSOs.


A systematic search for the hidden AGN in optically faint ULIRGs from AKARI catalog

Xiaoyang Chen

 

In order to construct a unique sample of ULIRGs at intermediate redshifts (0.5<z<1), we are conducting an optical follow-up program for 90-um FIR sources in the AKARI FIS Bright Source catalog with a large FIR/optical ratio (i-mag > 20). The cross-matched sample using AKARI-WISE-SDSS covers 7000 deg2, which is 10 times wider than the Herschel H-ATLAS FIR survey at the similar depth, which provides the capability to search for optically faint, FIR bright objects in a wide field at the first time. With a detailed analyses by spectral and SED fitting, we found that the energy contribution of AGN in optically-faint ULIRGs is smaller than that in the typical, optically bright (i-mag < 18) ULIRGs. The result indicates that the ULIRGs with a heavier obscuration (optically-faint) are possibly in the starburst-dominated early stage in the evolution of ULIRGs. Besides, the result also shows a positive correlation between AGN contribution and outflow velocity, implying that the AGN-induced powerful outflow plays an important role in the phase transition of ULIRGs. The study on the optically-faint ULIRGs is helpful to better understand the co-evolution of AGNs and their host galaxies during their most active period.


Clustering of optical and X-ray AGN in a semi-analytic model

Taira Oogi (Kavli IPMU)

 

Clustering of AGNs is regarded as one of the main observational constraints for AGN triggering mechanisms and gas accretion timescales. We investigate clustering properties of AGNs using a new version  of our semi-analytic model of galaxy and AGN formation. In the model we assume that a major/minor merger of galaxies and  disc instability trigger cold gas accretion on to a supermassive  black hole and AGN activity. Our model can reproduce the luminosity functions of AGN at z < 6.0. We find that the median host halo mass of bright X-ray selected AGNs  increases with cosmic time by an order of magnitude from z = 4  (log10(M/Msun) = 11.5) to z = 0 (log10(M/Msun) = 12.5). On the other hand, the median host halo mass of moderate luminosity AGNs increases from z = 4 (log10(M/Msun) = 11.2) to z = 0 (log10(M/Msun) = 12.7), and is above that of bright AGNs at z <~ 0.5. This trend is qualitatively in agreement with observational measurements. We also find that the median host halo mass of optical AGN depends only  weakly on the luminosity at low redshift and monotonically increase with luminosity. At high redshift, the median halo mass has significant dependence on the  AGN luminosity. In this presentation, we show the evolution of median host halo mass of optical and X-ray AGNs and two-point correlation functions of AGNs.


X-ray properties of z=4 HSC quasars

Masayuki Akiyama

 

TBD


Registration

 
Please visit the following page and register with a title and abstract of your presentation (oral/poster).
 

 
The deadline for submission of the abstract is September 30 while the deadline for registration is October 20.
Due to the time constraint, we may ask some participants to switch the presentation from oral to poster. We apologize in advance for this case.

Travel Support

 
NAOJ will provide a travel support for a limited number of participants (especially for students and young postdocs from abroad).
Those who wish the support should apply through the website when registering.

Conference Venue

 
The meeting will take place at Aoba Science Hall, Science Complex C 2F, Aoba-yama campus, Tohoku University, Sendai, Japan.
The access info of the conference place is given in the following webpage:
http://www.astr.tohoku.ac.jp/en/access/venue.html

Accommodation

 
Each participant needs to make hotel reservation by him/herself. Hotels around Sendai station or Sendai City Subway Tozai-line are most convenient.
 

Important Dates

 

  • ---29 Aug. 2018: First circular distribution
  • ---24 Sep. 2018: Second circular distribution
  • ---30 Sep. 2018: Deadline for the abstract and travel support request
  • ---20 Oct. 2018: Deadline for the registration
  • ---25 Oct. 2018: Final circular distribution
  • --2-3 Nov. 2018: This meeting

Organizing Committee

 

  • Masayuki Akiyama (Tohoku Univ., LOC chair)
  • Takuma Izumi (NAOJ)
  • Nobunari Kashikawa (Univ. of Tokyo)
  • Tomoki Morokuma (Univ. of Tokyo)
  • Tohru Nagao (Ehime Univ.)
  • Masahiro Nagashima (Bunkyo Univ.)
  • Yoshiki Toba (Kyoto Univ., SOC chair)
  • Keiichi Wada (Kagoshima Univ.)

Participant List

 

  • Masayuki Akiyama (Tohoku University)
  • Dani Chao (MPA)
  • Xiaoyang Chen (Tohoku University)
  • Andy Goulding (Princeton University)
  • Takuya Hashimoto (Osaka Sangyo University/NAOJ)
  • Wanqiu He (Tohoku University)
  • Kohei Ichikawa (Tohoku University)
  • Hiroyuki Ikeda (NAOJ)
  • Kohei Iwashita (Ehime University)
  • Takuma Izumi (NAOJ)
  • Ryota Kakuma (University of Tokyo/ICRR)
  • Nobunari Kashikawa (University of Tokyo)
  • Taiki Kawamuro (NAOJ)
  • Kojiro Kawana (University of Tokyo)
  • Satoshi Kikuta (Sokendai/NAOJ)
  • Mitsuru Kokubo (Tohoku University)
  • Shintaro Koshida (Subaru Telescope)
  • Kianhong Lee (Univ. of Tokyo)
  • Yoshiki Matsuoka (Ehime University)
  • Satoshi Miyazaki (NAOJ)
  • Takashi Moriya (NAOJ)
  • Tomoki Morokuma (University of Tokyo)
  • Tohru Nagao (Ehime University)
  • Masahiro Nagashima (Bunkyo University)
  • Mana Niida (Ehime University)
  • Akatoki Noboriguchi (Ehime University)
  • Shoji Ogawa (Kyoto University)
  • Kyuseok Oh (Kyoto University)
  • Kazuyuki Omukai (Tohoku University)
  • Taira Oogi (Kavli IPMU)
  • Maho Sato (Tohoku University)
  • Karin Shimodate (University of Tokyo/ICRR)
  • Hikari Shirakata (Hokkaido University)
  • John Silverman (Kavli IPMU)
  • Kazuyuki Sugimura (Tohoku University)
  • Shenli Tang (University of Tokyo)
  • Atsushi Tanimoto (Kyoto University)
  • Yuichi Terashima (Ehime University)
  • Yoshiki Toba (Kyoto University)
  • Hisakazu Uchiyama (Sokendai/NAOJ)
  • Yoshihiro Ueda (Kyoto University)
  • Bovornpratch Vijarnwannaluk (Tohoku Univ.)
  • Keiichi Wada (Kagoshima University)
  • Satoshi Yamada (Kyoto University)
  • Takuji Yamashita (Ehime University)
  • Atsunori Yonehara (Kyoto Sangyo University)

Contact

 
toba (at) kusastro.kyoto-u.ac.jp

subaru telescope

Targeted Research Fields

 
!!SMPLE!!
Infrared astronomy, Galactic astronomy and Astrophysics.

Last Update: October 31, 2018