Daniel	
  K.	
  Inouye	  Solar	  Telescope:	
  Collabora7ons	
  and	  synergies	
  between	
  DKIST	
  and	
  SOLAR-­‐C	
  
	
  
V.	
  Mar'nez	
  Pillet,	
  T.	
  R	
   immele	
  &	
  DKIST	
  Team	  Na9onal	
  Solar	  Observatory	
  )V\SKLY:LSLJ[LK(Z5:6»Z-\[\YL
	
  
	
  

Outline	  1. Where is Solar Physics Heading?
2. Why 4m?
3. DKIST Status
4. Solar-C & DKIST collaborations

2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	  2	  Where	  is	
  Solar	  Physics	
  Heading?	
  	
  Accurate	
  measurements	
  of	
  the	
  Magne9c	
  Field	
  from	  the	  interior	
  of	
  the	  Sun	  all	  the	
  way	
  into	  the	  Heliosphere	  	
  (Interior/Photosphere/Chromosphere/Corona)	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	  3	
  Measuring	
  B	
  in	
  the	  TR	  &	
  Corona	  • Forbidden	
  line	  FeXIII	  10747	
  Å	
  oﬀ	
  disk,	  Hanle	  saturated.	
  Stokes	
  V	
  from	  Zeeman	  • 10-­‐4	
  pol.	
  accuracy	
  was	
  needed	
  for	
  observa9ons	
  with	  arcsecs	  (texp	
  minutes	  !)	
  • MgII	
  h	
  &	
  k	
  line	  (2795	  Å):	  	
  upper	
  chromosphere	
  &	
  TR.	
  Stokes	
  V	
  expected	
  large.	
  k	
  
line	
  sensi9ve	
  to	
  Hanle	  eﬀect:	
  10-­‐100	
  G	
  ﬁelds.	
  • HI	
  Lyα	  (1215	
  Å)	
  oﬀ	
  disk	  will	  provide	  full	  vector	
  in	
  the	
  range	
  10-­‐100	
  G	
  for	  1	  Rsun	
  	
  	
  
• HI	
  Lyα	  (1215	
  Å)	
  on	
  disk	  transi9on	
  region:	
  full	  vector	
  in	
  the	
  range	
  10-­‐100	
  G	
  	
  
• Japanese	
  led	
  CLASP	
  experiment	  	
  Part I: direct coronal magnetic field measurement using NIR lines

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Explore	
  the	
  10-­‐4	
  limit	
  	
  

±	
  5	
  10-­‐4	
  2014/09/17	
  

±	
  5	
  10-­‐3	  Astronomica	
  Society	
  of	
  Japan	
  

5	
  

The	
  origin	
  of	
  the	  Quiet	  Sun	
  ﬁelds	  	
  4|V | Pillet	
  2013	  Mar'nez	
  
Ic

	
  
	
  	
  

Martı́nez González
et al.
Mar'nez	  González	  et	
  al.	  2013	
  Fig. 3.— Magnetograms of the two areas analyzed in this paper integrated for the whole observational period. The grey scale has beensaturated to show just the most strongly magnetized regions (otherwise, virtually all pixels in the FOV show a detectable signal above
noise level). Yellow patches show the average linear polarization signals after correcting from the bias according to (Martı́nez González
et al. 2012), and therefore, they are patches with a reliable detection of the transversal component of the magnetic field. Red circles show
the average position (between both footpoints) of the 219 (panel a) and 216 (panel b) small scale loops detected in both datasets. The
trajectories they follow while they evolve are comparable to the size of the circles. The two large areas covered by the dotted circles in panel
Dead
calm
areas in the quiet Suna) mark the two dead calm regions with a statistically significant lack of (detectable) magnetic loops. Note that they showlowmagnetic
activity too. Arrows indicate a few hotspots where several loops appear and disappear at approximately the same position, succesively
along an extended period of time.
voids, large circular voids seAt	
  10-­‐3	
  (satura9on)	
  large	
  voids	
  are	
  evident	
  in	
  deep	  magnetograms	
  250	
  loops	
  in	
  a	
  45x45	
  arcsec2	
  	
  FOV	
  and	  in	
  30	  minutes	
  Loop	
  emergence	
  is	
  not	
  uniformly	
  distributed	
  It	
  seldom	
  occurs	
  within	
  the	
  voids	
  These	
  voids	
  are	  very	  unlikely	
  (3	  10-­‐4)	
  100

The example in the fourth column is an example of twoloops appearing very close in time and in space. They
also disappear more or less at the same time, hence, one
could think this is an evidence of a sea-serpent magnetic
field line. Note also that the rightmost loop rotates.
All the observed dipoles are smaller than ∼ 1 Mm
(center-to-center distance between the two opposite polarity patches), becoming increasingly more abundant at
smaller scales, with most of the observed dipolar structures being ∼ 0.4 Mm (Figure 2a). This is barely threetimes the spatial resolution limit of IMaX, which suggeststhat the detection and our statistics might be limited by
the instrument. The tilt angle of these dipoles is uniformly distributed, meaning that it does not follow theHale’s polarity law. This last result is consistent with
Martı́nez González & Bellot Rubio (2009) and even withthe behaviour of the smallest ephemeral regions. As the
dipoles evolve, the separation between the footpoints ofthe structure fluctuates, increasing in the long run (seeFig. 2b). In average, the distance grows linearly withtime with a velocity of Vd = 0.9 km s−1 , comparable totypical granular values. This indicates that the loops passively follow the granular flows, as expected from weakmagnetic features (Manso Sainz et al. 2010).
The magnetic properties of these small dipoles are represented in Fig. 2c and 2d. They are obtaining inverting the data in the weak field approximation following
Martı́nez González et al. (2012). The magnetic flux has
been computed in the area containing the observed signal. The frontier has been defined by eye (as an isocontour of magnetic flux density) and hence is slightly

1.0

0.8
diﬀerent for the diﬀerent structures.
The magnetic flux
0.6
density is the mean value of the magnetic
flux densities in
0.4
this same 10
region. The magnetic fluxof the loops can be
0.2
explained with a power law using the exponent found by
Parnell et al. (2009). This means0.0that
populationof0
10 the20
30
40
50
small dipoles
follows the population of magnetic fields in1
the quiet Sun. But looking at the histogram of magnetic
flux densities, the loops are located at the end tail of thehistogram; it is mostly in the range 10-20 Mx cm−1 —i.e.,
0.1
10-20 G if the magnetic field were uniformly distributedand volume filling. This is compatible with the resultsof Martı́nez González et al. (2010) who state that, in the
0.01
quiet Sun, thelargersignal 30
the larger
0
10 the 20
40 the50degree ofA (Mm )
organization of magnetic fields.

N(A) (Mm-2)

•
•
•
•
•

Q 2 +U 2
Ic

2

Fig. 4.— Number of voids per unit area in the two datasets.
4. SPATIAL
Dark blue and cyan
histogramsDISTRIBUTION
correspond to the data shown in
Figures 3a and 3b, respectively. Solid line shows N (A) for a Poisson
Althoughsmall scale loops are found all over the obdistribution of points with n = 0.22 Mm−2 (we use a single value
servedareas,
their
spatialdistribution
notbothseem
since weobservealmostthe same
number of does
loops indatato
sets,
i.
e.,
248
and 249 loops).
window
representsthat,thebe completely uniform(Fig. The3). inset
It canbe observedof finding an area ≥ A. The x-axis is the area A inat probability
somelocations,loops
appearrepeatedly
andsucceMm2 .
sively as in bursts, forming clusters, a behaviour that has
been
beforeMartı́nez González
the noticed
first place,an byunambiguous
definition &ofBellot‘void’,Ruabionon-trivial(2009), who
the appearencetaskpointed
in itselfout(seethat,e.g., often,
Kauﬀmann& Fairallof 1991;
loops Tikhonov
made it more
likely that newoneslater de& Karachentsev
2006,
andwerediscussions
therein).
We On
adoptedthe simplest
definitionareas
here and
tectednearby.
the otherhand, extended
seem
only voidsof circulartheaslargestempty
to considered
be noticeably
empty
of suchshape:
events,if voids
apcircle inthat
be fitted in aHowever,given region
the point
field
pearedthecandistribution.
thisofmay
be deceiv—equivalently,
anempty
circlelimitedby
threepointsofing since voids arealso formed even in strictly uniform1
the distribution.
distributionsof points(Betancort-Rijo 1990, 1991).
the loops appearedon thesolar voids
surface,
A Ifquantitative
analysis uniformly
to determine
if thesearethen the probability of finding a void of area between A
statisticallysignificant was performed. This requires on
and A + dA within the field of view (square surface ofLoop	
  emergence	
  at	
  meso/supergranular	
  sizes?	
  Are	
  the	
  granular	
  ﬁelds	
  s9ll	  hidden	  (10-­‐4)	
  from	  our	  resolu9on/sensi9vity	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	  6	  area L2 ) would be (see Appendix):
P (A)dA =2(L − r)2(nA)2 −nAendA,abundant than a strictly ungest. Actually, for the para
vations, the probability oflager than A = 35 Mm2 (than 3.3 Mm) is very low
in Fig. 4). We conclude, ttical evidence for the two v
be real and not due to chandance of small voids is inte
structuring (see how loops aphenomena, in Fig 3).
In order to relate the divoids) to the global magneti
3 shows the integrated longand transverse (in yellow) m
servations. When dealing
one has to remind that it
transversal field component
tistically partially removed
bias for a percentile 95 whnoise (Martı́nez González etbias value depend on eachtensity profile). This meanmagnetic will be below thisof 95%. We have decided
than this bias to 0. Figure
significant patches of linear
the observed times. The p
seem to be clearly correlate
netogram, but the voids enc
magnetic activity than othe
ering the correlation with lithat most of the linear pola
tected are associated to loo
formation region.

5. DISC(1)

It is not yet clear what i8Manfred Schüssler

the energy-carrying eddies of the flow (i.e., the integral scale of the turbulence). Although
there is some dependence on the value of the magnetic Prandtl number (ratio of kinematic
viscosity to magnetic diﬀusivity), SSD action probably occurs in all turbulent flows of
suﬃciently high magnetic Reynolds number (see Brandenburg et al. 2012, and references
therein). While direct numerical simulations demonstrated SSD action in various settings
since the 1980s (e.g., Meneguzzi et al. 1981; Cattaneo 1999; Bushby et al. 2012), theeﬀect was also found in large-eddy simulations (Boussinesq or anelastic) in sphericalshells carried out to model the solar convection zone (Gilman & Miller 1981; Glatzmaier
1985; Brun et al. 2004). A. Vögler and M. Schüssler: A solar surface dynamo
L45
Comprehensive simulations of solar near-surface convection indicate that the observed
turbulent field could indeed be a product of a SSD action driven by the turbulent intergranular downflows (Vögler & Schüssler 2007; Pietarila Graham et al. 2010; Moll et al.
2011b). The characteristic properties of a magnetic field generated by a SSD can explain
the observed strong horizontal fields observed in the middle photosphere (Schüssler & Vögler2008) and the weak signals detected with sensitive polarimeters (Pietarila Graham et al.
2009; Danilovic et al. 2010a,b). While most of the field due to the SSD is of mixed polarity on small scales and has a strength of some tens to a few hundred Gauss, occasionallyenough unipolar flux is being assembled by the granular flows to form a kG flux concentration appearing as a bright point in the visible light. Therefore, observations of such
Vogler	
  et	
  al	
  	
  	
  2007	
  features in quiet internetwork areas on the Sun are consistent with SSD action.

The	
  origin	
  of	
  the	  Quiet	  Sun	
  ﬁelds	
  	
  
25	
  G	
  

3	
  G	
  

Intergranular	
  lanes	
  ﬁlled	
  with	  SSD	
  ﬁelds	  Fig. 2. Snapshot from the dynamo run C, taken about 5 h after introducing the seed field. The vertically emerging bolometric intensity (brightness,left panel) reveals a normal solar granulation pattern. The other panels show the vertical component of the magnetic field on two surfaces of
constant (Rosseland) optical depth, τR . Near the visible surface (middle panel, τR = 1, grey scale saturating at ±250 G), the magnetic field shows
an intricate small-scale pattern with rapid polarity changes and an unsigned average flux density of 25.1 G. About 300 km higher, at the surface
τR = 0.01 (right panel, grey scale saturating at ±50 G), the unsigned average flux density has decreased to 3.2 G and the field distribution has
become considerably smoother, roughly outlining the network of intergranular downflow lanes (darker areas on the left panel).

intermittency of the magnetic field at all heights. The strongest
magnetic features occasionally reach vertical field strengths beyond 1 kG near τR = 1.
Energy spectra for the vertical components of the nearsurface magnetic field and velocity as a function of horizontal
wave number, kh , are given in Fig. 4. The spectral magnetic energy shows a broad peak at kh ≃ 30, which corresponds to awavelength of about 200 km. At the high-wavenumber end of
the spectra, the magnetic and kinetic energies become less disparate. The remaining deviation from equipartition is due to theanisotropy resulting from the strong stratification.
We find that convective downward pumping of flux in fact
has a significant eﬀect on the energy balance of the dynamo, as
conjectured by Stein & Nordlund (2003). At any given height,
the time dependence of the horizontally averaged magnetic energy density, emag , is governed by the equation ∂t emag = WL −WJ −∂Pz /∂z. WL is the rate of work against the Lorentz force, WJ
is the Joule heating rate, and Pz is the vertical component of the
Poynting flux, the advective part of which measures the drainingof magnetic energy due to convective pumping. All quantities aremeant to be horizontal averages. The advective Poynting flux is
Fig. 3. Probability density function (PDF) for the vertical field component at three diﬀerent geometrical height levels. Dashed curve: z = negative throughout the convectively unstable parts of the sim−370 km (about 450 km below the visible surface); solid curve: z = ulation domain, confirming that any growth of magnetic energy
80 km (roughly corresponding to the average level of τR = 1); dotted in the system must have its source inside the domain. The diﬀuPz is foundaction
to be negligible
the convecting
layer.
Figurefroma ofsimulationof small-scalein theinsolar
near-surface
curve:
z = 4005.
kmSnapshot(about the averagelevel
τR = 0.01). Shownare sive part ofdynamo
timeaveragesover computational
about 20 minutes aroundt ≃ 4.5
In theandabsenceconvective
the diﬀerence
L − WJ
layers.
Thebox
is h.12 × 12 Mm2 wide
6.1ofMmdeep.pumping,
The panels
show Whorizonwould be a measure for the growth of the magnetic energy durtal cuts of the vertical field component (upper ing
panels;black andnegativeandthe exponential
growthwhitephase. indicates
In our case, morethan 80%
positivepolarity,
respectively)
and
of
the
verticalflowvelocity(lowerpanels;light
shadesindiofthis
diﬀerenceisindeedcarrieddownwards
by
means
of
the
surface τR = 0.01, about 300 km higher in the atmosphere,−∂Ptakenleavesthe box ofthroughbottomboundary.
cates
upflows,
dark
downflows).
Theandcutstermwere
a depth∼ 5 theMm(leftpanels)z /∂z andatthespatialdistributionof theshades
field is significantly
smoother
reduces
the growth
butas
does
more
associatedto the intergranular
downflow
lanes.
The However,andclosely
2.5 Mm(middlepanels) below
theaverageheighttheof eﬀectthe only
opticalsurface,as rate
well
atnot
the
dynamo action if the magnetic Reynolds number ismeanflux density
has(right
decreased
to about 3The
G. Thisstrong de- shut downfield
opticalsurfacepanels).
dynamo-generatedisassociatedwiththedownflowsin
suﬃciently
large.
crease indicates the absence of significant dynamo driving in the

2014/09/17	
  At	
  some	  sensi9vity	
  level	  all	  intergranular	
  lanes	  must	  be	
  ﬁlled	  with	
  mixed	  polarity	
  ﬁelds.	
  At	
  the	
  10-­‐4	
  level?	
  	
  Schussler	
  et	
  al	
  	
  	
  2013	  Astronomica	
  Society	
  of	
  Japan	
  

7	
  

Why	
  were	  Hinode	
  &	
  SUNRISE	
  successful?	
  	
  Resolu9on	
  &	  	
  photons	  l	
  <100	
  km	
  is	
  photon	
  mean	  free	
  path	  &	  Hp	
  (scale	
  height)	
  l=100	  km	  (	  φ ~0.1	
  arcsec)	
  requires	
  	
  	
  

texp ∝

φ/2
à	
  25	
  seconds.	
  Polarimetry	
  forces	
  it	
  to	
  be	
  25/4	
  ≈	
  6	
  s	
  
vc

Science	  requires	
  SNR ≈104	
  	
  	
  	
  (mo=	  -­‐10.7	
  magnitudes/arcsec2,	
  	
  	
  φ	
  	
  px	
  	
  	
  	
  =	
  	
  	
  	
  φ	
  	
  	
  	
  /	
  	
  2	
  	
  	
  )	
  

D=
2014/09/17	
  SNR
0.7N10−0.4m	  2
τΔλQtexpφ px

à D ≈ 4.6m	
  	
  	
  
	
  

Astronomica	
  Society	
  of	
  Japan	  We	
  need	  the	
  photons	
  !	
  
8	
  

DKIST:	
  4m	
  class	  	
  Spectropolarimetry	
  is	
  a	
  major	
  driver	  in	
  the	  design	
  of	
  our	  ﬂagship	
  facility	
  and	
  its	
  instrumenta9on:	  Clear	
  aperture	
  coronagraph,	
  imaging,	
  spectroscopy	
  and	
  polarimetry	
  of	
  rapidly	
  evolving	
  features	  	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	  9	  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

10	
  

5/20/2014

2014/09/17	
  

DKIST Construction - 19 March 2014

Astronomica	
  Society	
  of	
  Japan	
  

11	
  

	
  VBI	  :	
  Visible	
  Broad	
  band	  imager	  •Wavelength	
  range:	
  	
  380–900	
  nm	
  •Spa9al	  resolu9on:	  	
  0.03”	
  @	
  Hα	
  
•Spa9al	
  FOV:	   	  	
  2×2	
  arcmin2	
  •	
  Real-­‐9me	
  speckle	
  DKIST:	
  4m	
  class	  	  	  ViSP:	
  Visible	
  Spectropolarimeter	
  •Wavelength	
  range:	
  	
  380–900	
  nm	
  
•	
  Up	
  to	
  three	  lines	  simultaneously/fast	
  reconﬁg	  (10	  mins)	
  •Spa9al	  resolu9on:	  	
  0.03”/pixel	  •Spa9al	
  FOV:	   	  	
  2×2	
  arcmin2	  •Spectral	
  Resolu9on:	
  
	
  R	
  ~	
  	
  3.5	  pm	  at	
  630	  nm	  
	  VTF:	
  Fabry-­‐Perot	
  tunable	
  Spectropolarimeter	
  •Wavelength	
  range:	
  	
  520–860	
  nm	
  •Spa9al	  resolu9on:	  	
  0.03”	  •Spa9al	
  FOV:	   	  	
  1x1	
  arcmin2	  •Spectral	
  Resolu9on:	
  
	
  R	
  ~	
  3.5	  pm	  at	
  630	  nm	  
	
  DL-­‐NIRSP:	
  DiﬀracIon	
  Limited	
  NIR	  Spectropolarimeter	
  •Wavelength	
  range:	
  	
  900–2300	
  nm	
  •Spa9al	  resolu9on:	  	
  0.03-­‐1”/pixel	  •Spa9al	
  FOV:	   	  	
  2.4x1.8	
  arcmin2	
  	  	
  Cryo-­‐NIRSP:	
  Cryogenic	
  NIR	  Spectropolarimeter	
  •Wavelength	
  range:	
  	
  1000–5000	
  nm	
  •Spa9al	  resolu9on:	
  
	
  1”	
  (corona)	
  •Spa9al	
  FOV:	   	  	
  3x4	
  arcmin2	  	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

12	
  

DKIST	  	
  Instrument	
  Partners	  – University	
  of	
  Hawaii	  • CRYO-­‐NIRSP,	
   	
  PI:	
  Jeﬀ	
  Kuhn	  • DL-­‐NIRSP,	
  	
  PI:	  H.	
  Lin	
  – High	  Al9tude	
  Observatory	  • ViSP, 	  	
  PI:	  R.	
  Casini	  – Kiepenheuer	
  Ins9tute,	
  Germany,	  	
  • Visible	
  Tunable	  Filter,	
  MCAO	  Development,	
  PI:	  O.	
  vd	  Luhe	  – UK	
  (proposal	
  submiyed)	
  • Visible	
  Detectors,	  PI:	
  M.Mathioudakis,	  Belfast	  – Spain	
  (MOU	
  in	
  progress)	
  • Polarimetric	
  analysis	
  PI:	
  Jose	  Carlos	  del	  Toro	  Iniesta,	
  Granada	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

13	
  

Full	
  opera9ons	
  begin	
  in	
  2019	  perations NSO	  Remote	  Opera9ons	  Building	
  	
  
Y19 –
operations

NSO	
  Data	  Center	  	
  Boulder,	
  CO	
  )V\SKLY:LSLJ[LK(Z5:6»Z-\[\YL/VTL

Maui,	  HI	  ROB Schematic
design in progress!

9.8 M

7.2M
E

tudents, joint CU positions
EPO, AURA HR
d NISP DC positions

7M

2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

14	
  

DKIST	
  Opera9ons	
  
	
  	
   a	
  space	
  mission”!
“operate	
  more	  like	  Access	  Mode	  Service	  Mode	  Facility	  Mode	  • PI present"• Dedicated time"• PI runs facility"• Proprietary data"• PI at remote site"• Dynamic scheduling"• RA runs queue "• Open data policy"• No PI"• Dynamic scheduling"• RA selects program "• Open data policy"

Install New Instrument"
Inst. Scientist Training""

Nominal Science Mode"

Test/Develop new Programs""~ 10%"~ 80%"

"
"
"
"

"
"

~10% ??"DKIST operates ~ space missions: DKIST+Solar-C common TAC?
2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

15	
  

Solar-­‐C	
  &	
  DKIST	  collabora9on	  Lyα image of the UVCS slit

DKIST	
  will	  measure	
  the	
  Coronal	  magne9c	
  ﬁeld	  in	
  these	  cri9cal	
  areas.	
  	
  Perhaps	  using	
  as	
  yet	
  unknown	
  spectral	  features	  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

16	
  

Solar-­‐C	
  &	
  DKIST	  collabora9on	
  The variation of Cn2 (h) with altitude is usually divided into two distinct "layers":

1. Ground Layer: ground-level effects like wind-surface interactions, diurnal solar heating,and various man-made effects at the telescope (e.g., "dome seeing")
2. Free Atmosphere: everything above the ground layer. An increase in the freeatmosphere Cn2 often seen at ~10km is due to strong wind shear at the Tropopause.
This plot above is the basis for saying that Mt. Graham, like many astronomical sites, has asignificant component "ground layer seeing".
Using the parameterization of Fried, the phase structure function can be written
DI (r ) 6.88 r / r05/ 3

r0 is the Fried Parameter (also called the "coherence length"), defined as
r00.185O 6 / 5 cos3/ 5 ] ª¬ ³ Cn2 (h)dh º¼

3/ 5

where ] is the zenith angle (]=0 at the zenith and S/2 at the horizon), O is the wavelength, and his the height above the ground. The Fried parameter is a measure of the aperture over which
there is approximately 1 radian of rms phase aberration, so it is a crucial parameter for describing
the "seeing" through a turbulent atmosphere.

CaII	
  H	
  imaging:	
  A	
  Hinode	
  success	
  story	
  	
  
The	
  blue	  is	
  hard	  from	  the	
  from	  the	
  ground:	
  AO	
  has	  a	
  much	  harder	
  job	  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

17	
  

Solar-­‐C	
  &	
  DKIST	  collabora9on	
  Solar-­‐C	
  &	
  DKIST	  collabora9on:	
  the	
  next	  	
  Golden	
  Age	
  for	
  Solar	
  Magne9sm	
  2014/09/17	
  Astronomica	
  Society	
  of	
  Japan	
  

18	
  

有難う 御座います2014/09/17	
  Astronomica	
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  of	
  Japan	
  19