An observational study of cosmological evolution of High- z AGN jet - PowerPoint PPT Presentation

An observational study of cosmological evolution of High- z AGN jet Yosuke FURUYA (Yamaguchi univ.) Collaborators : Kenta FUJISAWA, Kotaro NIINUMA, Hiroki TURUTA, Masaki MATSUDA (Yamaguchi univ.) East Asia VLBI Workshop 2018 @ PyeongChang, Korea

Introduction: Size of High-z AGN jet

High-z source has size ~10 3 times smaller EVN_Newsletter_40_web.htm than Low-z one. http://www3.mpifr-bonn.mpg.de/div/vlbi/newsletter/40/ Do AGN jets evolve cosmologically? M87; z = 0.0042 10 kpc Low- z 1 pc Cygnus A; z = 0.056 1 kpc Boccardi+ 2015 30 J1026+2542; z = 5.3 @ 5 GHz J1427+3312; 33 12 42.6 20 z = 6.1@1.6GHz High- z 0.20 42.4 10 42.2 0.15 Flux Density (mJy/beam) Declination (J2000) 0 42.0 0.10 -10 41.8 100 pc -20 0.05 41.6 100 pc 1 kpc -30 41.4 0.00 -40 41.2 Frey+ 2013 14 27 38.64 38.62 38.60 38.58 38.56 38.54 Right Ascension (J2000) -50

Are the jets confined to dense gas in the early → Because of having highly doppler boost universe? However, with the large beam size… Confined or boosted? (← Which effectes?) Comparing local universe, On the other hand A Confined jet model & observations ・the material density is (1+ z ) 3 times larger. ・The density of CMB energy is (1+ z ) 4 times larger. (Ghisellini+ 2016) Others 13% FSRQ is majority type of AGNs at z > 4.5 Wide-double FSRQ 7% 43% SSRQ 37% (Coppejans+, 2016)

Gas density High ・Jets form hotspot in the compact region with sharp edge, and no jet outside of the hotspot. Gas density Low ・Jets form defuse structure → High-frequency → High-resolution → High-dynamic range observation High Density Low Density Core Hotspot Core Defuse jet structure The environmental effect

Gas density High Let’s Observe by EAVN! Core Hotspot Core Low Density High Density → High-dynamic range observation ・Jets form hotspot in the compact → High-resolution → High-frequency ・Jets form defuse structure Gas density Low and no jet outside of the hotspot. region with sharp edge, Defuse jet structure The environmental effect

bias in archive data!! An observational J0906+6930 was detected as point-like. Only 2 High-z sources were observed at high-freq. so far. Images & redshift dependence J0906+6930; z =5.47 S (a) Peak 42 mJy/bm Peak 63.6 mJy/bm (33) r.m.s. 0.2 mJy/bm r.m.s. 0.25 mJy/bm C 22 GHz 43 GHz (28) L (5) X Q 100 pc K (18) (1) (Zhang+, 2017) (Romani+, 2004) (1) y 10 29 r 3 < z < 6 a n 10 28 i Luminosity (W/Hz) m y 10 27 r i a l e n r 10 26 i P m @9 - 12 GHz (rest freq.) 10 25 i 3.5 l 6.0 6.5 3.0 4.5 5.0 5.5 7.0 4.0 e Redshift r P

caused by environmental effect. Whether the evolution of AGN jet is We observe High-z AGN jets at high-freq. and discuss the dependence between size of radio structure and redshift. The purpose

Observation: JVN/EAVN large survey

Yosuke. F Yosuke. F JVN survey Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F The sources detected by JVN. ・Target: ・Purpose: Obtain the VLBI images. EAVN imaging Yosuke. F for EAVN observation. Select the suitable sources ・Purpose: JVN/EAVN observations Mizusawa 20m ●●●● Japanese VLBI Network Hitachi 32m ●●● ● 6.7 GHz ● 8.4 GHz ● 22 GHz ● 43 GHz ●●● Takahagi 32m ●●● Hitachi 32m ●●● Yamaguchi 32m ●● Yamaguchi 32m ● Takahagi 32m ●●● Usuda 64m ●● Iriki 20m ●●●● Iriki 20m ●●● Usuda 64m ●● Kashima 34m ●●● Ishigaki 20m ●●●● Ishigaki 20m ●● Gifu 11m Kashima 34m ●●● ● ・Target: 522 sources with z > 3 Ogasawara 20m Gifu 11m ● ●●●● gasawara 20m ●●● An Tao+ 2018

JVN survey Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F ・Purpose: Yosuke. F Yosuke. F Yosuke. F Yosuke. F The sources detected by JVN. Select the suitable sources for EAVN observation. (←Now!) EAVN imaging ・Purpose: Obtain the VLBI images. ・Target: JVN/EAVN observations Mizusawa 20m ●●●● Japanese VLBI Network Hitachi 32m ●●● ● 6.7 GHz ● 8.4 GHz ● 22 GHz ● 43 GHz ●●● Takahagi 32m ●●● Hitachi 32m ●●● Yamaguchi 32m ●● Yamaguchi 32m ● Takahagi 32m ●●● Usuda 64m ●● Iriki 20m ●●●● Iriki 20m ●●● Usuda 64m ●● Kashima 34m ●●● Ishigaki 20m ●●●● Ishigaki 20m ●● Gifu 11m Kashima 34m ●●● ● ・Target: 522 sources with z > 3 Ogasawara 20m Gifu 11m ● ●●●● gasawara 20m ●●● An Tao+ 2018

Observation: JVN/EAVN large survey

→ 522 sources ・Estimated flux at 8.4 GHz from FIRST is higher than 4 mJy. ・Redshift is higher than 3. ♦ Selection criteria Number - redshift in our sample Our sample ・No VLBI detection. were selected The selection of targets 300 200 Number 100 0 3.0 4.0 Redshift

Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F Yosuke. F JVN survey Yamaguchi Hitachi Total time 70 hr (7 epoch) Frequency 8192 - 8704 MHz Bandwidth 512 MHz (Ch1) Pola. RHCP T sys ~ 50 K ~ 30 K ●● Yamaguchi Hitachi (@EL) (40 deg) (85 deg) Resolution 10 mas Sensitivity 3 mJy (7 σ ; 6 min) Correlatior GICO3 (Yamaguchi) Obs. date 2017/12/05 16:45 - 03/15 (1 ep) (UT) 2018/06/28 03:15 - 13:15 (2 ep) • 2 epoch observations ware conducted. • 143 targets were surveyed in the obs. This survey will be finished until next spring.

Result: Interim report of JVN survey

74 out of 143 sources were detected over 7σ!! Spectral index Redshift Our sample 74 sources Corr. flux 1.4 - 8.4 GHz Detected sources • ~10mJy is majority. • z > 4 → 7 sources, 3 < z < 4 → 68 sources y r a y 250 30 25 r n a i y m y n 200 20 r r i a i m a y l 20 e n r n 150 15 i Number r i a l m i y e P m n r r i i a P l i 100 10 m e l e n 10 r i r i P l m e P 50 5 r i P l e 0 0 0 r P 3.0 3.4 3.8 4.2 4.6 5 15 25 35 45 50- -1.0 0.0 1.0 Redshift Flux density (mJy) Spectral index

74 out of 143 sources were detected over 7σ!! 53.9/141.4 KVN VERA Tianma NRO45 KVN 42.7/63.7 95.2 15.4 36.4 VERA 53.9 22.4 mJy 54.6 Tianma 11.9 14.7 - 8.4 NRO45 - - - - (7σ@43GHz) mJy (7σ@ 22GHz) 22GHz -> 13sources detectable by EAVN, 43GHz -> 10 sources Estimated flux densities @ 22/43 GHz • The sources 15 S 22GHz S 43GHz • KVN - Tianma • KVN - Tianma • VERA - Tianma • VERA - Tianma 10 • NRO45 - Tianma Number 5 0 0 15 30 45 0 15 30 45 Estimated flux density (mJy)

by EAVN ✓ JVN／EAVN obs.: We plan to do new large surveys to obtain high-quality images of High- z sources with, ① High-frequencies ② High-resolution ③ High-dynamic range ✓ Question: Do the structures of AGN jets depend on redshift? ✓ Now: Doing JVN survey to select suitable sources for the EAVN observation. → Currently, 74 sources were detected. Conclusion 143 sources 522 sources 72 sources detected To be observed