Here you can see the last log before the first black screen and error message:
Jul 4 14:08:15 yoann-boss1983.home coreaudiod[427]: 2015-07-04 02:08:15.951988 PM [AirPlay] Power: SystemWillSleep
Jul 4 14:08:15 yoann-boss1983.home coreaudiod[427]: 2015-07-04 02:08:15.952291 PM [AirPlay] BTLE client stopping to browse for AirPlay Solo Target Presence.
Jul 4 14:08:15 yoann-boss1983.home watchdogd[167]: [watchdog_daemon] @( pm_callback) - ref=0x0 msg_type=0xe0000280 msg=0x3f0004
Jul 4 14:08:15 yoann-boss1983.home watchdogd[167]: [watchdog_daemon] @( wd_daemon_thread) - events buffer: 59r1129 3709s1129 3770r11372 7849s11372
Jul 4 14:08:15 yoann-boss1983.home coreaudiod[427]: 2015-07-04 02:08:15.953044 PM [AirPlay] BTLE discovery removing all devices
Jul 4 14:08:15 yoann-boss1983.home coreaudiod[427]: 2015-07-04 02:08:15.954043 PM [AirPlay] BTLE client stopped to browse for AirPlay Solo Target Presence.
Jul 4 14:08:15 yoann-boss1983.home blued[85]: Release the WiFi lock
Jul 4 14:08:15 yoann-boss1983 kernel[0]: Sound assertion in AppleHDAFunctionGroup at line 1250
Jul 4 14:08:36 yoann-boss1983 kernel[0]: PM response took 5182 ms (51, powerd)
Jul 4 14:08:36 yoann-boss1983 kernel[0]: Failed to get hibernate image filename
Jul 4 14:08:36 yoann-boss1983 kernel[0]: ARPT: 7869.843407: AirPort_Brcm43xx::powerChange: System Sleep
Jul 4 14:08:36 yoann-boss1983 kernel[0]: ARPT: 7869.843417: wl0: powerChange: *** BONJOUR/MDNS OFFLOADS ARE NOT RUNNING.