.
RR Lyrae stars: new discoveries in the OGLE data
Radosław Smolec (CAMK PAN, Warsaw)
Henryka Netzel (Warsaw University)
Igor Soszyński (Warsaw University)
IAU General Assembly 2015
Focus Meeting 17: Advances in Stellar Physics from Asteroseismology
RR Lyrae stars: new discoveries in the OGLE data
1
Optical Gravitational Lensing Experiment, OGLE, 1992–
I
Warsaw University project
I
now OGLE-IV (since 2010)
I
more than 100k classical pulsators
in LMC, SMC and Galactic bulge
photo: www.astrouw.edu.pl
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
2
Blazhko Effect in double-mode RR Lyr stars
-0.4
-0.2
0
∆I [mag]
0.2
0.4
0.6
0.8
1
1.2
1.4
5200
5400
5600
5800
6000
6200
time [d]
6400
6600
6800
Soszyński et al. (2014), Smolec et al. (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
2
Blazhko Effect in double-mode RR Lyr stars
-0.4
-0.2
0
∆I [mag]
0.2
0.4
0.6
0.8
1
1.2
0.755
1.4
0.750
5400
5600
5800
? majority of the modulated
RRd stars have atypical period ratio
? multiperiodic modulation is
present
6000
6200
6400
one, two, three,
0.745
time
[d] modulation periods
P1O/PF
5200
OGLE-IV Galactic bulge RRd stars
6600
6800
0.740
0.735
0.730
0.725
0.720
-0.50
-0.40
-0.30
-0.20
log PF
Soszyński et al. (2014), Smolec et al. (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
3
5200
6000 6200
time [d]
6400
6600
6800
1O
5600
5800
6000
6200
time [d]
6400
6600
6800
7000
0
0.8
0.6
0.4
0.2
0
0.8
0.6
0.4
0.2
0
0
A0 [mmag]
PB2
A1 [mmag]
A [mmag]
A [mmag]
PB1=209.8d
7000
F
5400
40
30
20
10
0
120
80
40
0
120
80
40
0
PB1
0.01
0.02
frequency [c/d]
0.01
0.02
0
φ0 [rad]
5800
PB2=322.9d
8
6
4
2
PB2
φ1 [rad]
2
0
-2
-4
5600
30
20
10
0
A [rad]
8
6
4
2
F
A [rad]
A0 [mmag]
φ0 [rad]
120
80
40
1O
0
5200 5400
φ1 [rad]
120
80
40
0
A1 [mmag]
Blazhko Effect in double-mode RR Lyr stars
2
0
-2
-4
PB1
0
frequency [c/d]
1
phase
2
1
2
phase
? both radial modes may be modulated with the same period, but
? more commonly, dominant modulation for the fundamental mode has different period than dominant modulation for the first overtone
Smolec et al. (2015)
?
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
4
A [mmag]
Blazhko Effect in double-mode RR Lyr stars
? amplitudes and phases of the
radial modes vary irregularly
on a long time-scale of a few
hundred or thousand days
100
80
60
40
φ [rad]
OGLE-III
OGLE-IV
3
2
F mode
1O mode
2500
3500
4500
time [d]
5500
6500
? the short-term modulations are
also irregular
Smolec et al. (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
4
A [mmag]
Blazhko Effect in double-mode RR Lyr stars
? amplitudes and phases of the
radial modes vary irregularly
on a long time-scale of a few
hundred or thousand days
100
80
60
40
φ [rad]
OGLE-III
3
2
F mode
1O mode
A [mmag]
2500
120
3500
4500
time [d]
5500
6500
F mode
1O mode
40
OGLE-III
? the short-term modulations are
also irregular
? OGLE-BLG-RRLYR-13442 has
switched the pulsation mode
(RRab→RRd; Soszyński et al.
2014)
80
0
4
φ [rad]
OGLE-IV
OGLE-IV
2
0
-2
2500
3500
4500
time [d]
5500
6500
Smolec et al. (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
5
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
0.76
F+1O: 1335
Soszy
ński et al. (2009,-10,-11)
.
0.74
0.72
F+1O
F+2O: 9 stars
Chadid
al. (2009),
.Poretti etet al.
(2010),
PS/PL
0.70
0.68
.Benkö et al. (2010),
.Guggenberger et al. (2011)
.
0.66
0.64
1O+?: 23 stars
Gruberbauer
et al. (2007)
.Olech & Moskalik
(2009)
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
.Soszyński et al. (2009)
.Süveges et al. (2012)
.Moskalik et al. (2011, -15)
.Chadid (2012), Szabo et al. (2014)
.Molnar et al. (2015)
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
5
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
0.76
F+1O: 1335
Soszy
ński et al. (2009,-10,-11)
.
0.74
0.72
F+1O
F+2O: 9 stars
Chadid
al. (2009),
.Poretti etet al.
(2010),
PS/PL
0.70
0.68
.Benkö et al. (2010),
.Guggenberger et al. (2011)
.
0.66
0.64
1O+?: 170 stars
Gruberbauer
et al. (2007)
.Olech & Moskalik
(2009)
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
.Soszyński et al. (2009)
.Süveges et al. (2012)
.Moskalik et al. (2011, -15)
.Chadid (2012), Szabo et al. (2014)
.Molnar et al. (2015)
.Netzel, Smolec & Moskalik (2015a)
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
5
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
0.76
F+1O: 1335
Soszy
ński et al. (2009,-10,-11)
.
0.74
0.72
F+1O
F+2O: 9 stars
Chadid
al. (2009),
.Poretti etet al.
(2010),
PS/PL
0.70
0.68
.Benkö et al. (2010),
.Guggenberger et al. (2011)
.
0.66
0.64
1O+?: 171 stars
Gruberbauer
et al. (2007)
.Olech & Moskalik
(2009)
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
.Soszyński et al. (2009)
.Süveges et al. (2012)
.Moskalik et al. (2011, -15)
.Chadid (2012), Szabo et al. (2014)
.Molnar et al. (2015)
.Netzel, Smolec & Moskalik (2015a)
.Smolec et al. (2015, Bl-RRd)
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
5
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
0.76
F+1O: 1335
Soszy
ński et al. (2009,-10,-11)
.
0.74
0.72
F+1O
F+2O: 9 stars
Chadid
al. (2009),
.Poretti etet al.
(2010),
PS/PL
0.70
0.68
.Benkö et al. (2010),
.Guggenberger et al. (2011)
.
0.66
0.64
1O+?: 189 stars
Gruberbauer
et al. (2007)
.Olech & Moskalik
(2009)
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
.Soszyński et al. (2009)
.Süveges et al. (2012)
.Moskalik et al. (2011, -15)
.Chadid (2012), Szabo et al. (2014)
.Molnar et al. (2015)
.Netzel, Smolec & Moskalik (2015a)
.Smolec et al. (2015, Bl-RRd)
.Jurcsik et al. (2015)
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
5
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
0.76
F+1O: 1335
Soszy
ński et al. (2009,-10,-11)
.
0.74
0.72
F+1O
F+2O: 9 stars
Chadid
al. (2009),
.Poretti etet al.
(2010),
PS/PL
0.70
0.68
.Benkö et al. (2010),
.Guggenberger et al. (2011)
.
0.66
0.64
1O+?: 304 stars
Gruberbauer
et al. (2007)
.Olech & Moskalik
(2009)
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
.Soszyński et al. (2009)
.Süveges et al. (2012)
.Moskalik et al. (2011, -15)
.Chadid (2012), Szabo et al. (2014)
.Molnar et al. (2015)
.Netzel, Smolec & Moskalik (2015a)
.Smolec et al. (2015, Bl-RRd)
.Jurcsik et al. (2015)
.Netzel, Smolec & Moskalik (2015b)
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
0.64
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
0.63
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
Px/P1O
93% of RRc/RRd observed from space (13/14)
0.64
Galactic bulge, Netzel et al.
M3, Jurcsik et al.
0.62
0.62
0.61
0.61
0.60
0.60
0.20
0.30
P1O [day]
0.40
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
• additional modes are non-stationary
Netzel, Smolec & Moskalik (2015a,b)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
0.64
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
0.63
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
Px/P1O
93% of RRc/RRd observed from space (13/14)
0.64
Galactic bulge, Netzel et al.
M3, Jurcsik et al.
0.62
0.62
0.61
0.61
0.60
0.60
0.20
0.30
P1O [day]
0.40
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
• additional modes are non-stationary
Netzel, Smolec & Moskalik (2015a,b)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
93% of RRc/RRd observed from space (13/14)
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
• additional modes are non-stationary
4.0
3.0
2.0
1.0
0.0
4.0
3.0
2.0
1.0
0.0
4.0
3.0
2.0
1.0
0.0
4.0
3.0
2.0
1.0
0.0
4.0
3.0
2.0
1.0
0.0
4.0
3.0
2.0
1.0
0.0
A (mmag)
OGLE-BLG-RRLYR-09305
P1O=0.30295d
A (mmag)
OGLE-BLG-RRLYR-09126
P1O=0.32399d
A (mmag)
OGLE-BLG-RRLYR-08826
P1O=0.31251d
A (mmag)
OGLE-BLG-RRLYR-07806
P1O=0.31900d
A (mmag)
OGLE-BLG-RRLYR-06802
P1O=0.31830d
A (mmag)
OGLE-BLG-RRLYR-06610
P1O=0.31623d
0.6
Netzel, Smolec & Moskalik (2015a,b)
0.61
0.62
P/P1O
0.63
0.64
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
0.68
0.66
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
0.64
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
P4O/P1O, P3O/P1O
93% of RRc/RRd observed from space (13/14)
0.62
0.6
Z=0.0001
Z=0.001
Z=0.01
0.58
0.56
0.2
0.25
0.3
0.35
P1O [day]
0.4
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
• additional modes are non-stationary
Netzel, Smolec & Moskalik (2015a,b)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
93% of RRc/RRd observed from space (13/14)
0.004
OGLE-BLG-RRLYR-08597
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
0.002
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
0
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
0.004
0.6
0.61
0.62
0.63
0.64
1.2
1.22
1.24
P/P1O
1.26
1.28
0.002
0
• additional modes are non-stationary
Netzel, Smolec & Moskalik (2015a,b)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
6
Non-radial modes in RR Lyr stars: 0.61–0.63 period ratio
• common form of RR Lyr pulsation:
93% of RRc/RRd observed from space (13/14)
38% of M3 RRc/RRd stars (Jurcsik et al. 2015)
3% of OGLE-III Galactic bulge stars, but
27% in the two high cadence OGLE-IV fields
• three sequences in the Petersen diagram
up to three non-radial modes in a single star
• additional mode(s) must be non-radial
• subharmonics of additional mode(s)
are present
• additional modes are non-stationary
4.0
3.0
2.0
1.0
0.0
OGLE-BLG-RRLYR-07806
P1O=0.31900d
A (mmag)
2010
4.0
3.0
2.0
1.0
0.0
2011
4.0
3.0
2.0
1.0
0.0
2012
4.0
3.0
2.0
1.0
0.0
2013
4.0
3.0
2.0
1.0
0.0
all data
0.6
0.61
0.62
P/P1O
0.63
0.64
Netzel, Smolec & Moskalik (2015a,b)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
7
New class of double-periodic RR Lyr stars: gravity mode pulsation?
0.76
F+1O: 1335
0.74
0.72
F+2O: 9 stars
F+1O
PS/PL
0.70
1O+?: 304 stars
0.68
0.66
0.64
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
7
New class of double-periodic RR Lyr stars: gravity mode pulsation?
0.76
F+1O: 1335
0.74
0.72
F+2O: 9 stars
F+1O
PS/PL
0.70
1O+?: 304 stars
0.68
?+1O
0.66
0.64
1O+?
0.62
0.60
F+2O
0.58
-0.60
-0.50
-0.40
log PL
-0.30
-0.20
?+1O: 12 stars (11 OGLE+1 Kepler), Netzel, Smolec & Dziembowski (2015)
Period of the additional mode is longer than 1O period. It is longer than
period of the (undetected) F mode!
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
8
New class of double-periodic RR Lyr stars: gravity mode pulsation?
• dominant pulsation: radial first overtone
• very narrow range of period ratios
• additional mode is always coherent
• it must be a non-radial mode of gravity (or mixed) character
• instability range extends slightly below F mode frequency, but no obvious
selection mechanism can be proposed
Netzel, Smolec & Dziembowski (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
8
New class of double-periodic RR Lyr stars: gravity mode pulsation?
• dominant pulsation: radial first overtone
• additional mode is always coherent
0.689
0.68 stars
KIC9453114
0.688
P1O/Px
• very narrow range of period ratios
0.690
0.687
0.686
0.685
0.684
0.683
• it must be a non-radial mode of gravity (or mixed) character
0.682
-0.5
-0.45
-0.4
-0.35
log Px
-0.3
-0.25
-0.2
• instability range extends slightly below F mode frequency, but no obvious
selection mechanism can be proposed
Netzel, Smolec & Dziembowski (2015)
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015
RR Lyrae stars: new discoveries in the OGLE data
9
.
Honolulu, IAU GA, FM17: Advances in Stellar Physics from Asteroseismology, 12-14.08.2015