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SlingshotprominencesevolutioninCoolStars
CAROLINAVILLARREALD’ANGELO,MOIRAJARDINE,ANDREWCOLLIERCAMERON,VICTORSEE&ROSEWAUGH
CoolStars20– Boston2018
ΩΩ Ω
Coolcondensationofmassco-rotatingwiththestar
• FirstseenonABDor(Collier-Cameron+1989,1990)• ΩAB Dor=0.5d• prominencelifetime=1-2d
Radialacceleration
2
H⍺intensity
-vsini vsiniVelocity
Coolcondensations
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
3
Forcebalancetosupportprominences
• Materialwillaccumulateinapotentialminima(Ferreira+2000,Jardine+2001)
• Radialforcebalancemustoccur(CollierCameron+1989)
CentrifugalForce
Ω
RK RA
Enforcedco-rotation
MagneticTension
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Whereareslingshotprominencesfound?
CoolStars(VillarrealD’Angelo+2018)+Massivestars(Petit+2015)
RK < RA
RK > RA
Slingshot prominences
No slingshot prominences
4SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Sun
ABDor
5
Whereareslingshotprominencesfound?
CoolStars(VillarrealD’Angelo+2018)+Massivestars(Petit+2015)
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Timeevolution?
Sun
ABDor
6
Oldersolarlikestarcan’tsupportprominences
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Sun
ABDor
7
AsolarlikestarwillhaveRk=RAwhenProt~6days
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Slowrotatorscan’tformprominences?
Ω%& ⟶ ~376Myr (50th)Ω%& ⟶ ~797Myr (90th)10thneverreachtheΩ%&
Johnstone+(2015)andTu+(2015)
100 101 102 103
Age [Myr]
100
101
102
⌦[⌦
�]
10th
50th
90thRk = RA
Slingshotprominences
NoslingshotprominencesSun
8SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
Ω%& = 4.6Ω⨀
Evolutionofprominencemass
𝜌0~𝐵2
4𝜋𝑅51
[Ω2𝑟 − 𝐺𝑀⋆/𝑟2]
100 101 102 103
Age [Myr]
1012
1013
1014
1015
1016
1017
1018
Pro
min
ence
mas
s[g
]
50th
90th
Max.massrange:[10@A − 10@B]g.
9
𝑚D ∝ 𝜌0
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
VillarrealD’Angelo+2018a,2018b(inprep)
��D ∝ ��⋆
100 101 102 103
Age [Myr]
10�1
100
101
Pro
min
ence
lifet
ime
[day
s]
50th
90th
Evolutionofprominencelifetime
Max.ejectiontimerange:[1-14]days.
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO 10
𝑡D =HI
HI
VillarrealD’Angelo+2018a,2018b(inprep)
100 101 102 103
Age [Myr]
1012
1013
1014
1015
1016
1017
1018
Pro
min
ence
mas
s[g
]
50th
90th
HKAqr (dM1.5)
Pz Tel(G6.5)
LQLup (G8IV)SpeedyMic(K3V) TWA6(K7)
V410Tau(K3)ABDor (K2V) Solarprominences
Prominenceobservedinabroadrangeofages!
100 101 102 103
Age [Myr]
10�1
100
101
Pro
min
ence
lifet
ime
[day
s]
50th
90th
11SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
ResumeSlingshotprominences:• Predictedmassesandlifetimesagreewithobservations.• PresentuntilthelateheavybombardmentforourSun.
Whydowecare:• Slingshotprominencecantracethecoronalstructure(poster 149).• Helpustoestimatethemasslossrateofthestar(poster149).• Dotheyinfluencetheevolutionofplanetaryatmosphere?.
12SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
THANKYOU!
13SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
0 20 40 60 80 100 120⌦[⌦�]
0
5
10
15
20
25
30
35
40
R[R
�]
Rk
RA
Rk = RA
Ω%& = 4.6Ω⨀
RK andRAasafunctionoftime
Rotationalevolutionmodelforasolarlikestar(Johnstone+2015)
Slingshotprominences
Time
14SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
15
Prominencemodel
dA*dAm
dr
hm
𝑀D =J∗LM∗N
OP∗
M∗MQ
2𝐹 𝛻��, 𝛻𝜑 ,(�� = W
MQ)
��D =��∗4𝜋𝑅∗2
2𝑑𝐴∗
𝜏D =𝑀D
��D
(VillarrealD’Angelo+2018)
SLINGSHOTPROMINENCEEVOLUTIONINCOOLSTARS- CAROLINAVILLARREALD'ANGELO
